The Apple TV won’t be replacing my trusty Mac mini at any point in the near future, but it certainly is pretty cool. For $99 you get a tiny little black box that you would be hard pressed to say is anything but worth the money. There are certainly cheaper places to get a lot of the same content, but not a single other place to get as good of an experience and as quickly as you can with the Apple TV.
I don’t have a television, but if I did, I think I’d come to the same conclusion.