I don't see how this is any different than simply watching videos on cnn.com. I have a Mac connected to my big screen TV and I also have an AppleTV (which I inherited from someone else). I have yet to see where the AppleTV provides me anything more than I can already get with the Mac itself.
Its the convenience that makes it a better experience. Why would I want to have to use a web browser on a full pc attached to a tv when I could use a small box with a remote, tv designed ui and lower electricity use than an always on laptop?