That being said, after watching this video it struck me how little innovation has being going on in the email space.
Granted, change for change's sake is not always a good thing, but for a video made before I was born it seems strange that even the mail.app that ships with Lion still hasn't fundamentally changed from its neXt forebears - we still have the three large horizontal textboxes on top of a large textarea for the body, and everything seems to function in exactly the same manner.
No wonder people my age barely use email anymore. A subject line? really?