We try to avoid excessive posts about FCC filings that may or may not be for Android goodies coming to the US, but this one was a dead giveaway for AT&T. Just take a look:
The guys over at WirelessGoodness dug up this picture from a recent FCC filing, and it clearly shows the device is either a Tab 10.1 or 8.9, and that it has the official AT&T 4G LTE logo. Hard to call that a "rumor." It seems likely that AT&T will announce the device before the holiday season.