Stefan Pollard explains what's the difference between Sender ID and SPF in this ClickZ article. Here's the summary:

The Sender ID and SPF protocals are almost identical in syntax. They differ in how the receiver domain looks up your authentication record, which is a line of code inserted in your DNS record that appears in your e-mail message headers.

SPF checks are performed against the domain from the envelope's return-path address, typically called the bounce address. Sender ID checks are performed against the purported responsible address (PRA), that is, the visible sender address in the message.

Let's say the domains in those addresses are the same. Then you as the sender can pass a Sender ID check with only an SPF record. If the domains are different, you should create both records and place them in the corresponding domains.

When in doubt, place your SPF record in all domains you have control over. This increases the chance the record will be placed where the receiver is checking.

Hotmail has been the most vocal Sender ID advocate. Recently, it issued guidelines for creating a record and the mechanisms to avoid. Hotmail has specifically requested senders not to use the PTR (define) mechanism. It also recently asked senders to use a hard fail " -all" at the end of their records to indicate their e-mail infrastructure is secure.

One last note on implementing Sender ID and SPF: It's not uncommon for a sender to change IP addresses or providers. Most ISPs will perform authentication checks on inbound e-mail by directly querying your DNS zone.

Hotmail asks senders to notify it when they make changes, allowing it to cache the records. This makes authenticating senders and applying reputation scoring easier for Hotmail.

If you've changed your Sender ID and SPF records recently, use the following URL to update Hotmail: http://support.msn.com/default.aspx?productKey=senderid&mkt=en-us.

In some cases, if the Sender ID/SPF record contains syntax errors, Hotmail will even send an e-mail to alert you of the problem so you can make corrections before you have delivery problems.

Source: ClickZ

While behaviorally targeted mailings may not have the same reach and sales as promotional marketing messages, they meet customers' needs with personalized, relevant information. Often, these communications are triggered at various points in the purchase process and customer lifecycle. These messages may be part of a longer series aimed at building relationships beyond just one purchase. The objective is to create the kind of communications that are so relevant they break through inbox clutter and are read and acted upon.

When looking for areas that provide opportunities to develop a targeted series of e-mail communications, examine the following:

Welcome e-mail. A welcome e-mail can jump-start buying. Many e-mail marketers take advantage of this highly read messaging. Depending on your product, tailor an offer that engages prospects. The initial e-mail must build the relationship with users. The idea is to get prospects engaged while they're still excited about your offering.

Purchase-related e-mail. As part of the purchase-confirmation process, provide customers with a series of e-mail messages to ensure the product has arrived and the customer can get the most out of it. Include references to information on your site or blog providing product and customer support. Use these communications to sell related products and services, such as coordinated clothes or warranties. Airlines and hotels send reminders that aid trip planning while providing other related services, either their own products or related suppliers.

Post-purchase e-mail. Product purchase is a trigger for future communications. Think like a direct-response TV marketer who uses an initial sale to promote related products. This can work in a number of ways, such as selling more ink for a printer. Or you can make recommendations based on past purchases, as Amazon does.

Purchase-behavior-related e-mail. Take a cue from traditional direct marketers who segment customers based on past buying behavior. Communications to consider:

• High-value buyers. This group is the core of your customer base and must be handled with care. Assess their potential based on past purchasing. Look at the type of product they buy as well as the dollar amount and frequency of purchases.
• Low purchasers. These customers and prospects may no longer be interested in your offering. Consider ways to either reengage them or eliminate them from your e-mail list, because at some point they may consider your communications spam.
• Gift buyers. These buyers may only be interested in your offering at the next gift-giving event that's relevant to the recipient. If you can determine this, provide a reminder; but don't clutter their inboxes with ongoing, irrelevant e-mail.
• Gift recipients. These folks are your target market and probably like your product. Consider ways to add them to your house file.

Reminders/calendar-related e-mail. Consider the marketing calendar from a customer perspective. Take into account personal events, such as birthdays, anniversaries, and vacations, or business events, like conferences and budget season. Brainstorm relevant personal events and position reminders as a service. Help customers plan ahead and provide them with useful, relevant information. The more information customers share with you, the less likely they are to buy from competitors. Shopping with your firm will be easier.

Source: ClickZ

• Takeaways from the "ClickZ Specifics: Email Marketing" event
• E-mail: Time for a Makeover
  More notes from the Clickz Email Marketing event this week
• Hotmail asks: Are your subscribers engaged?
  Craig Spiezle, Microsoft's Director of Online Safety Technologies, shared his insight on how to ensure a top deliverability reputation at a recent Exact Target event.
• Mailing to corporate domains
• What to Look for in a Bulk E-Mail System
  For most organizations there are significant pitfalls and costs associated with a homegrown email sending system. The risks may vastly outweigh the rewards.
• Email Marketing Platforms Buyer's Guide 2007
  new edition of E-consultancy's buyer guide - focus on UK
• Automatically generate inline styles
  Campaign Monitor points us to a tool that takes an HTML document and transforms the CSS styles in the head to inline styles. Pretty cool stuff!
• Deliverability Wisdom from ClickZ Specifics Conference
  more conference notes
• Email and Lead Generation
  Is email list rental a good way to do acquisition?
• How A Pretty Face Can Push Visitors Away
  The direction in which the model's eyes are facing in your creative  is very important
• Call for Speakers: MarketingSherpa's Email Summit & Expo Seeks Speakers
• Going Green: How to Transition Catalog Users to Email & Lift Conversions 19%
• How to Conduct Email Surveys - Tips to Lift Response & Write Subject Lines
• Anti-Phishing Phil
  A game that teaches people to identify (and avoid being tricked by) phishing websites. Thanks for finding this one Justin!

• Say goodbye to eBay and PayPal fraudsters
  Thanks Matt for finding this one: Yahoo now blocks the delivery of unauthenticated eBay and PayPal emails through DomainKeys.
• Strategies for Centralizing Email - webinar
  David Daniels makes recommendations for maximizing the benefits of centralizing marketing, customer service and transactional email.
• Cut Through E-mail Clutter With These Format and Design Tips
  practical formats and design tips to help marketers cut through e-mail clutter
• The Relevance Trajectory
  I highly recommend downloading and reading this white paper on how to make your emails more relevant.

• Going retro with e-mail creative
  Andrew Osterday suggests we make a movement back to the beginnings of e-mail where text dominated and images were kept to an absolute minimum.

Email is at once a ubiquitous and embattled medium because its dependability and trustworthiness are under attack by spam, viruses, phishing, and often inexact ISP filtering; yet it could get worse if email marketing is not centralized within the enterprise, according to a StrongMail/JupiterResearch executive survey.

Some 93% of executives surveyed say their company has deployed some type of email marketing solution, and permission email marketing now accounts for 27% of the email that consumers receive in their primary personal inboxes - up from 16% in 2003, according to the study. (View the webinar here)

JupiterResearch’s “Maturation of Email: Controlling Messaging Chaos Through Centralization” provides insight into the current state of messaging deployments and argues that as the use of email is increasing, few companies control message frequency, analyze subscriber behavior, and coordinate their messaging initiatives across channels and business units - and as a result marketing strategies will be undermined to the detriment of brands.

Among the findings of the report:

• Some 38% of executives said their email messaging endeavors are centralized in one location, with 24% citing that six or more departments manage it separately. (Takeaway: Such a lack of coordination and centralization often leads to over-mailing subscribers and messages that lack a consistent tone in branding and style.)
• 44% of executives are aware that email would be more effective if it were managed from one platform.
• Just 26% agree that it is easy for them to understand how often they are communicating with their clients. (Takeaway: Companies must begin to align their email spending and infrastructure to not only leverage additional cost efficiencies but also allow for more rigorous control of messaging across the enterprise.)

Email challenges:
One-third of executives surveyed work with an outsourced provider, and 30% use an on-premises packaged application.

(Takeaway: Given the disparate ways email is now managed and the paltry budget dollars often assigned to what is a critical medium, marketers must align infrastructure and labor resources to work with the channel.)

Email budget allocations:
Most companies have yet to deploy a commercially available enterprise-class email system, with 31% of companies surveyed using a homegrown application for their email marketing needs.

(Takeaway: Homegrown solutions are typically based on email servers and appliances that are ill-equipped to provide needed functionality, including deliverability and frequency controls, targeting, and measurement insight.)

• The M20: Top Marketer Blogs: October 2007
  update of the M20 - and I'm still at number 3 :)
• Alert: Rendering problem in Yahoo Mail Classic

In this article Gail Goodman gives us a couple of tips on how to build your list:

1. Add a "Join My E-mail List" sign-up box on your website.
Your website is usually the first place people look when they want information about your business. Don't miss the chance to start building a relationship with them when they visit your website.

2. Ask your customers for their e-mail addresses and permission.
Whether it's over the phone or in person, tell customers about your e-mail communications and ask if you can add them to your list. If you have a physical store, put out a sign-up book in a prominent place. If your business is internet-based and your only customer communication is through e-mail, send a follow-up e-mail after an order and ask if they want to join your list. If you have employees who interact with customers, train them to ask as well.

3. Ask those you meet at networking events and at trade shows.
When you meet people at networking events and trade shows, tell them about your free e-newsletter or your e-mail-only specials and ask if they would like to join your list.

4. Offer incentives for signing up.
It's amazing how a freebie or a chance to win a prize can be just what a person needs to "take the plunge" and sign up for your e-mail list. Your giveaway doesn't have to be costly; it can be as simple as sharing your expertise in the form of a free white paper or guide. Make it clear to those who sign up that they will be added to your list.

5. Run a "Forward to a Friend Contest."
In your e-mail newsletter, let your contacts know that if they use the "Forward to a Friend" link to send this month's newsletter to at least one new recipient, they'll be entered into a drawing for a prize. An e-mail marketing service provider lets you see which subscribers forwarded your e-mail to a friend.

6. Partner with a related business or organization.
Think of a business or organization that's related to your business, but isn't a competitor. Work together to promote each other's e-mail communications to your customers. Some good partnership examples are a tax accountant and a financial planner, a public relations firm and a website designer, or a theater and a nearby restaurant. Highlight your partner as a guest writer in your newsletter and ask that they do the same for you. At the end of each article, invite readers to join that author's e-mail list.

7. Include a "Join My E-mail List" link in all online content.
Do you have articles on your website or on other websites? Do you have your own blog? This is another great opportunity to add people to your list. Include a link that takes readers to your sign-up page. Your copy could read, "Like this article? Get more like it in your inbox. Subscribe today for our monthly e-newsletter."

8. Include a "Join My E-mail List" link at the bottom of your e-mail signature.
This is great advertisement and it's free. Add one line that describes the benefits of your newsletter or e-mail promotions like, "Get our monthly newsletter with tips on how to grow your business" or "Receive weekly coupons for exclusive discounts."

9. Promote your e-mail communications in all printed materials (including your business cards).
It's easy to forget about e-mail when doing a printed piece. Whether it's a brochure or a direct mail postcard, don't forget to add a line asking the receiver to sign up for your free newsletter. Business cards are a great place for a quick promo as well.

Source: http://www.msnbc.msn.com/id/21083965

by Stephanie Miller

I believe it's misleading to think about email's contribution without factoring in the risks of batch and blast, complaints, irrelevancy and acquisition costs.

That's a downer, you say. Not at all. I find it inspiring because it means that email success and ROI is a direct result of our ability to build a relationship with our subscribers. Email, done well, creates the kind of relationship that drives incremental revenue, loyalty and word of mouth.

To get there, we need to be honest with ourselves. Let's say you are sending 5 emails a month, about once a week. Your CFO says, "We need more revenue, send more email!" (This happens pretty often, unfortunately.) So you send twice as much, 10 messages a month. That is now two emails a week per subscriber. Voila! The revenue number at the end of the month goes up, probably 30% to 50% (based on what I've seen with clients). Everyone is happy, right?

Well, maybe not everyone. Look at your unsubscribe rate. Check the complaint rate (subscribers clicking the "this is spam" button). Both will rise when you send more email. The cost to replace these subscribers and maintain your file size will cut into that incremental boost - you have to count this acquisition cost in your figures. Plus, in every case we've seen, the non-responder rate (subscribers with no opens or clicks) also goes up dramatically.

It's not so hard to see why. When we abuse the trust that subscribers put in us and send more email than could possibly be relevant, subscribers tune all our messages out. Even if they don't unsubscribe or complain, but they basically unsubscribe with their delete button. These subscribers are now lost to us.

Add up all that collateral damage, and the ROI boost may be much less or even negative.

I'm a huge fan of sending more email, but only when the subscriber is "in market." How do you know who's in market? By understanding the buying cycles and life stages of your subscribers.

Think about subscribers who ...

• Just signed up for email
• Are ready for product or service renewal
• Recently purchased
• Visited a particular section of your website
• Abandoned their shopping cart
• Clicked but didn't convert
• Downloaded a whitepaper
• Haven't opened or clicked in the last quarter

All these lifestage points are great opportunities for tailored email messages. Even if the number of subscribers in each category is small compared to your total file size, the response rates on targeted, high relevancy offers will blow away your normal rates. These additional messages will not only increase relevancy, drive new revenue and build higher value in your email program (which drives future response), they will improve your brand, lower complaint rates, improve deliverability and make you better looking (seriously - success will make you glow!).

Calculate your email program ROI to include acquisition as well as list quality factors. Review it not just as a whole but also at the subscriber level (or at least by key segment). You'll have a much more realistic picture of how you can optimize.

Source: http://www.returnpath.biz/resources/archives/2007/10/email_roi_is_mo.php

In his latest Email Insider column, David Baker a look at the top five functional reasons to communicate with your customers and offers some really great tips on how to get creative on the messages:

5. To fulfill or confirm an order.
Can you add some creativity to standard emails?  This can be as easy as modifying your template with a holiday theme, or having fun with the messaging. For example: "Santa thanks you for your order; it's less for him to carry down the chimney."  People appreciate humor and creativity, and your team can have a lot of fun with this.

4. Promote your site, product, or service.
When you promote your company, do you tie your USP to a theme? A creative voice gets the most attention in the inbox. Try a few options with your promotional strategy. Tactics like countdowns to Christmas got a lot of traction last year in the retail space, but think outside of that and come up with some witty metaphors to wrap your product/service around. Imagine a product promotion that's a surprise only to be opened on the site or tied to an instant win, or sweeps with pick-a-present under the tree. Check your calendar. There are over 20 events from October to January to which you can tie a theme, each unique and with different audiences.

3. Deepen the loyalty to your site or brand.
Think about the considerations involved in making your consumers enthusiastic supporters and evangelists of your brand. They need a "container" to carry your message and build on it in their own social mechanisms. Is it a refer-a-friend / share component or an incentive to share?  Think outside the box and bring a creative metaphor to the table. It could be putting their face on "Sexiest Man Alive" on the cover of People magazine, or a comical photo-sharing contest — anything to create additional value that can travel. Instead of thinking solely about your communication goal, think about enabling the community of customers. Remember, Halloween is the most prolific photo-sharing event of the year; how many ways could you take advantage of this community event with your product or service?

2. Introduce your brand or acquire a customer.
It's tough to brand amidst the noise of the holiday season. This puts more pressure on you to create great acquisition messaging and programs that are fun, engaging, and have the ability to be shared and syndicated. Whether it's a list rental, partner email, sponsored email or your own prospect list, this is the time to be creative with themes. Remember, though, they may not know your brand well enough to understand an off-the-wall metaphor, but that doesn't mean they won't appreciate a bit of fun and humor in your messaging. Remember the first time you traveled on Southwest Airlines and you got a sarcastic response from the flight attendant? You were a little shocked at the candor, but worked yourself into enjoying the experience.

1. Thank them for their patronage.
Did you know that the type of email that gets the highest open rate is an apology letter? The personal touch is widely appreciated, yet we reserve it for mistakes only. We all want to be recognized, so personalized notes thanking customers for their patronage to your brand is a worthwhile effort. A brand can't live on direct promotion alone - there needs to be a little massaging of your messaging to show you aren't a robot marketing arm sending to the masses. This is ideal for a New Year's e-mail, thanking them for a year of loyal patronage to your brand. It's also very easy to tie a reward to this message.                         

The most successful opt-out page I've ever seen was for Milwaukee Best Beer. It had a super-attractive female asking if you were sure you wanted to opt out. For men, that was a reaffirmation of why they were on the site in the first place. An opt-out page doesn't have to be a lost cause.  You could have Santa ask them if they are sure they want to be taken off his list. Satire and humor give color to your brand. Play with it and you'll be amazed at the feedback you get.

Source: Email Insider