The big picture is that the Apple TV has the potential to change the way we obtain and consume video and, to a lesser extent, audio. It's very easy to get the media you want--provided the iTunes Store offers it--and while HD movie rentals can't be viewed the instant you click the Rent button, with a reasonably fast broadband connection you need plan no more than an hour ahead to watch a fine-looking and -sounding movie on a big screen with big sound. In its current state, the Apple TV isn't without its quirks, but many of them are minor or could be addressed with a software update or modification to the Store's movie rental agreement.
If you've stayed away in the past because of the Apple TV's dependence on your computer, you wanted HD video and 5.1 sound and couldn't have it, or you simply couldn't imagine why you'd need another box tethered to your TV, it's time for a stern rethink. This is an important and useful piece of technology.