I think its great, I have a huge Itunes library though. If your looking to rent Hd movies, its good for that too. Not bad over all and the rentals are inline with DBS companies ppv movies.
I may be looking in this direction myself since the Rescue Me premiere is tonight, and Dish Network still doesn't have FX in HD. And I'll download all the seasons I missed in between.
Take a look at the Popcornhour products. Welcome To Popcorn Hour These units are priced much lower than AppleTV and play back all of the popular video formats.
I bought the model A100 when they first came out and added a 500 gig hard drive. It's an excellent media player.