1) Probably the most annoying, the screen on the legend destroys the desire. It shouldn't on paper, but believe me it does. The pentile matrix vs no pentile matrix is abundantly clear.
2) I am terrified of dust getting under the screen because i can see the gap between the screen and phone and am constantly making sure I clear dust from it. On the legend the screen is sealed to the side of the phone.
3) Well obviously the materials aren't as nice, but I knew that would be the case in making the change so that one does not really count.
That being said, the desire is a powerful beast and I am looking forward to Froyo.
These might be interesting points to someone tossing up between the two phones. The legend was also blazingly quick, and unless you want to play the latest 3d games, it is probably fast enough for you. Still not sure if I did the right thing upgrading!