Review: Pantech Pocket for AT&T
The Pocket covers all of the messaging basics. It runs the stock messaging (SMS), email, Gmail, and GTalk apps. All of them work well, though they don't present any new features.
There’s no support for third-party instant messaging, so you'll have to scout through the Android Market to find the right IM apps.
The Pocket comes with both the full Facebook and Twitter apps, as well as some handy widgets for both.