Outlook 2007 email rendering

Outlook 2007 uses Word 2007, and not Internet Explorer to render HTML emails. This has the following implications:

How does this impact on your emails?

Things that have changed Outlook 2007	Is this an issue?	Impact
No support for animated gifs		The image will be rendered as static, only the first frame will display. Ensure your animated gifs have a link in the first frame.
No support for Flash or other plug-ins		Email was not designed for Flash, this is not a new issue as it has always been a problem.
No support for CSS floats/positioning		Not best practice – This has been an issue with a number of the webmail clients such as Hotmail, Gmail and Yahoo.
No support for using images as bullet in unordered lists		Easy work around using a table instead of an unordered list. This may be slightly more difficult for non technical users.
Background images will not render		Not best practice – Due to issues with other webmail clients such as Hotmail, Gmail, and Yahoo.
Forms will not display properly		Not best practice – Forms have been a problem with previous versions of Outlook and other webmail clients such as Hotmail, Gmail, and Yahoo.
Poor background colour support		Only an issue if using background colour in nested tables.
Alt tags will be modified		Keep Alt tags concise and to the point. Start them with descriptive copy so if they get cut off…