While I enjoy my iPhone, I have no use for AT&T. They have engaged in false marketing, their networks are of dubious reliability, and–quite frankly–the only thing they have going for them is their exclusive contract with Apple for the iPhone.
There are lots of new phones entering the market. HTC has a couple fine Android phones. Google has its Nexus One, which–in my estimation–is overpriced. One thing I am noticing, though: other than the iPhone, AT&T is not offering the leading-edge phones. And, given that they are about to lose their exclusive hold on the iPhone, it remains to be seen what moves they have up their sleeve.
And one more thing: when my contract is up, I’m ditching the iPhone for a Droid.