FCC documents revealed that an unannounced phone may be coming to AT&T. The FCC documents showed that the frequency band is GSM 850/900/1800/1900 and 3G 850/1900 which confirms it for AT&T.
The Bluetooth Special Interest Group was also registered at the same time, naming it the "Pantech Android Phone". This is the first time hearing about this phone so nothing else is know about it, but this does look to be a low-end device. Expect more information to leak out as we get closer to an expected announcement date.