According to sources reporting, "AT&T and Microsoft are rolling out a new feature to U-Verse broadband platform that will enable U-Verse subscribers to use their Xbox 360 as a U-Verse receiver. Since U-Verse allows for 4 HD connections on a subscription, this nullify the need for another receiver for your gaming setup. This means AT&T U-verse customer's Xbox 360 will have a Dashboard app, and when launched, it'll let it function exactly like any other U-verse set-top. The only major catch is that it can't be the only set-top -- you'll need at least one DVR at another TV in the house to enjoy one of the four HD streams that could be funneled into your home."
The roll out will begin in early Nov'7th, and the only prerequisite is that you already have one AT&T DVR box somewhere in the house; the Xbox can't be your only receiver.
Another tipster has chimed in with some interesting slides -- looks like your Xbox will need a hard drive!