I saw an interview with Teh Steve recently where he gave some numbers regarding battery life with Edge versus 3G. It was pretty dramatic and clearly the reason why we don't have 3G yet.
Who's "we"? I have 3G coverage all over the place here in MA, both UMTS (3G) and HSDPA (3.5G) and use it every day with my 8525 (which is running modded WM6 and actually shows me the U or H or E icon depending on which service I'm using)