I honestly can't imagine how this would be useful. Think about it, the whole idea behind
TV is to stream content to your living room, from your mac on the other side of the house. That's what I do. In my entertainment system, I have a PS3, HD DVD player,
TV, and DirecTV box. I can't imagine wanting to get up walk to the other side of the house, load up a dvd into my iMac, and then go watch it from the living room when I have all the equipment right there. It's just not practical. Even if I could, I'd lose a lot of functionality of a DVD player using the
TV to watch it. What if I want subtitles, or what if I want the DTS track? Even if the
TV got an add-on DVD player to plug into the USB port on the unit, the software would have to go through a huge revision to provide this functionality. The remote is also limited as well.
Digital downloads are the future of content. Apple is not trying to reinvent the DVD player.