Matt Vernhout just posted this message on his excellent blog:
Updates to the documentation include:
- New guidelines for legitimate email avoid being mistaken for image-based junk mail.
- List permission and opt-in recommendations have been amended to reflect current best practices.
- User-unsubscribe processes have been clarified.
along with a number of other updates to the document.
This is a great document to read as a marketer, and should set the bar for your marketing programs.