First, I think ALL cell phone carriers are overrated for their data transmissions...not to mention plain old fashioned "service" to make a call. There are so many factors in ANY data transmission technology and it kills me that consumers don't have enough brainpower to think about all the things that can possibly AFFECT any kind of transmission...especially wireless.
I think 3G and any other data "provider" is still far in its infancy in the USA (especially compared to Europe)...as well as some consumers feel they should be able to walk outside and get a 20Mbit connection on ATT like they do at home on their cablemodem. Over time speeds will improve and we'll all be able to use our "phones" 99.9% of the time in the car or next to a waterfall. That day, however, is likely 10+ years away.
I really don't use my iPhone much (2 hours a month?) on non-WIFI...even though I live in the burbs there seem to be enough WIFI places for me to connect to IN THE EVENT that I actually want to pick up my iPhone and do something. And I'm 39. I'm sure all the 14-24 year olds out there want to use the phone 23 hours a day as it's the fad of the decade... but for us folks that actually work and have things to do (and be in an office with plenty of WIFI and computers) 8-9 hours a day, I'm gonna guess a lot of us aren't out there complaining night and day about any cell carrier coverage.

I'm not being snippy...I'm stating a fact regarding demographics.
I'm not slamming anybody here...just stating some opinions.
-Eric