Some interesting info coming out of the requisite Apple TV teardown from iFixit. First off, the Apple TV has an 8GB Samsung Flash chip but room for another 8GB (v2 1080P version?). While most of that space is probably reserved for caching movies, a few apps could use this space to build a home. The Panasonic board that contains the Broadcom Wifi chip also has an FM radio. Apple could enable this at some point, or someone hacks like the Droid 2. Same A4 and 256 MB of RAM as the iPad or iPod touch.
And finally, a curious array of connections that coincidentally lines up with Apple's 30-pin dock connector: