I agree that the xbox coupled with xbmc is a fantastic video playback device. It uses a video player called mplayer which has handled every crazy video format I've thrown at it. However, unless I'm doing something wrong, it's not the best for viewing dvd images. It will play the .vob files, but only one at a time (you need to play 2-3 of them per movie). It also will not allow you to navigate menus on the dvd (though I'm pretty sure this feature is being worked on). If you are ripping your dvd's to divx (or whatever) then xbox is fantastic, but for playing images of backed up dvd's I think you need to wait a while.
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