The interface on my webmail software feels like a mail client should -- easy navigation, threaded conversations, multiple window panes, and it's fast. Google on the other hand took years before they could be bothered to add buttons to Gmail, and even now Gmail's interface is an ugly monument to 90's era design principles.
Uh, in 2004 when Gmail launched it was one of the first widespread AJAX apps. It made Hotmail / Yahoo feel like molasses, gave you 200x storage, and added the idea of labels instead of folders. They obsessed tremendously over performance to make it usable by people who hitherto had only been able to tolerate desktop mail clients.
Now I realize a lot of things change in 6 years, but hell, Dreamhost is still using SquirrelMail. The author just throws it out there like amazing webmail is a foregone conclusion, yet I've not seen any webmail that beats Gmail even by a little bit. Can someone enlighten me?