More Than Just a Hobby
Apple keeps saying the Apple TV is just a hobby but it seems to me to be more of a way for Apple to be able to find out how people are using their TV.
Case in point - this Thursday you'll be able to watch a Paul McCartney concert live on your Apple TV, as well as through iTunes. With the Apple TV in place, Apple can quickly figure out how many people will go to their TV for an event like this or just watch it on their computer.
It also gives Apple an easy way to test out their content deliver system on a smaller scale than what they'd have to be able to push out if they actually did release a full blown TV of some sort.
I have no doubt that Apple is going to make a bigger play for the media room of homes in the near future - but the Apple TV is a great way to test the waters and get valuable insight into how people are actually using their TVs in 2012.