Evolution, the e-mail client that's part of the GNOME desktop, will be seeing many significant changes during the GNOME 3.4 development cycle.
Matthew Barnes has blogged
about some of the changes that can be expected from the Evolution 3.4 release next March when GNOME 3.4 is to be released.
Among the new features to be expected from Evolution 3.4 is porting Evolution's email rendering to WebKit/GTK+ rather than the old GtkHtml, automated account setup support, porting the reset of the GConf keys to GSettings, a new Microsoft Exchange back-end, a new back-end for Kolab Groupware, and saner account storage. There's also going to be a new D-Bus service for email.
These changes should be nice for anyone using GNOME's Evolution e-mail client rather than Mozilla Thunderbird or the other open-source alternatives.