I honestly can't imagine how this would be useful. Think about it, the whole idea behind
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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,
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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
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TV to watch it. What if I want subtitles, or what if I want the DTS track? Even if the
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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.