Simple answer: If you're disappointed with AT&T's lineup of device offerings, go find a different carrier and don't complain about it. Complaining doesn't get anyone anywhere with AT&T.
Longer answer (a more "corporate" response, if you will): AT&T will launch new devices in time. "In time" meaning that it could be tomorrow, or it could be next year. Right now they're more concerned with making the 3G network more widely spread in the US, so you might see new equipment being launched in the near future.