Listing of Popular Mail Clients
Mail clients to test against for Functionality and HTML mail
Below is a chart of Mail clients that were used to post to a mailling list that I have been subscribed to. It was a snapshot of the mails that were sent in during the month of February 2004.
With a bit of effort, this listing could provide a basis for starting a survey of mail client rendering functions. I believe this is a critical piece of information that could be used to gather an understanding specifically of how HTML mail is handled in each of these clients.
Obviously, this list is not exhaustive. It should be added to and similar lists should be generated from other mailing lists and other mailboxes. If you have a large .mbox file or mail archive that has mails from many different people, please consider sending it to me so that I may extract additional clients and begin to establish some additional stats for them. At some point in the future, I will put these into a database that could handle annotations for the client, and specifically note the differences in versions.
If you would like to add clients or have additional thoughts, please post them to the Wiki Discussion Board.