I'm gonna call it now. Apple TV will be dead or practically irrelevant for those of us who have an iOS device or two. And once it does, there will be an app on your iPhone or iPad called Apple TV. It'll likely just be called "TV" for simplicity's sake. And via Airplay, you'll be able to drive content to future Apple high resolution displays.
If you think about it now, the Apple TV really is a hobby. It's there because Apple needs us as beta testers to see how we use television of tomorrow and how we interact with content via our phones and tablets. It's really all that is about at this time.
Once Apple has figured out how to go forward, and according to Steve Jobs, they have, I'm pretty sure it doesn't involve the Apple TV hardware as we know it. And that is precisely why the Apple TV will go away.
In the near future, Apple displays will not only support Retina Display or higher resolution than today's HDTV but it'll support Airplay can connect directly to iOS devices and Macs without going through the routers. Essentially, isn't that all we really need the Apple TV for today? It's Airplay function?
For non-Apple displays, Apple will probably release an Airplay hardware with HDMI connector and nothing more. In fact, Apple may license Airplay to other display and HDTV makers so that they can work with Apple's iOS devices.
And to drive media and games to your big Apple, your iOS devices are all that you need.