In my opinion, I think Yahoo has so far the best email client among the three major web-based email providers (Yahoo! Mail, GMail, and Hotmail or Windows Live! Mail). The only problem that I have with that is that there is no mechanism for organizing emails as conversations (the only way of organizing mail in GMail). About Hotmail, the less said, the better. They should change their web-based user interface for Hotmail, to the one they use for Outlook, which is very, very nice.
However, I came across an interesting senario in Yahoo. If you right click on one of your mails, the browser’s context menu appears over the context menu of the email client. There is a clash between the browser’s context menu and the context menu for the AJAX application. Perhaps context menus in AJAX apps are not the right UI element. See the picture below for an example in Firefox.
Interestingly enough, this does’nt happen with IE7. See the figure below.
Safari does’nt support Yahoo’s AJAX version