Campaign Monitor analyzed 6 months of data covering more than 250 million opens. The result - a birds eye view of email client popularity and usage trends over time. Check it out here.
What I found most interesting to see is the total market share held by the 5 most popular email email client over the last 6 months. Seems like the adoption of Outlook 2007 is growing slowly but steadily...
Tamara Gielen is an independent email and digital direct marketing
consultant with over 10 years of experience in online, email and direct marketing. 
No AOL, man they have really lost market share in the email space
Posted by: Alex Williams | Mar 25, 2009 at 05:32 PM
Thanks for promoting the report Tamara, much appreciated
@Nazzareno Being in the early adopter market, you'd actually be very surprised how low the usage is for email clients like Gmail and Thunderbird in the larger market. Even if we're only looking at click data.
Although image blocking can have an impact on the results, when you compare month to month data, Gmail and Thunderbirds market share has actually been consistently shrinking for the last few months. It will be interesting to see if this trend continues over the coming year.
Posted by: Dave Greiner | Mar 25, 2009 at 04:18 AM
Yep... unfortunately since most clients now do not automatically render images, that data is almost too inaccurate. That's why big names are missing (Gmail, Thunderbird, Aol...), while others are very low.
Using click through instead of opens, at least the web email clients could be better compared.
Posted by: Nazzareno Gorni | Mar 24, 2009 at 04:44 PM
I think that looking at the click through log instead of opens log, it would have more accurate data. Some big names could appear (Gmail, Thunderbird, Aol...).
Posted by: Nazzareno Gorni | Mar 24, 2009 at 02:18 PM
I just wish Microsoft products would die. Does make me sad that Outlook family is still in the top 5, even with the small print considered.
Posted by: Jake Holman | Mar 24, 2009 at 11:01 AM
hi Tamara,
Mark had pointed out the 'fine print' - which is something to take into consideration too.. I deffo think it impacts on Outlook 2007 (as in there are more using it than is showing)
>>>from the link you posted::::::
The fine print
The email client a person is using can only be detected if images are displayed. This can give an inflated weighting to email clients that display images by default, such as Outlook 2000 and the iPhone. It will also provide a lesser weighting to those that block images by default such as Gmail and Outlook 2007. Those email clients that aren't capable of displaying images, such as older Blackberry models and other mobile devices cannot be included in this study. [end]
Posted by: denise cox | Mar 24, 2009 at 09:48 AM