Crisper graphics, there's no goddamn blur during the fights which the xbox version has, no goddamn bloom lighting at night time which is fucking annoying and done absolutely sloppy on the xbox version, Japanese voice acting which really adds to the game's atmosphere despite the fact it's not in japan;etc.
the only thing xbox version has over the dc version is better load times and better textures on some objects. the visual upgrades overall, are fucking anoyying, especially the blur during fights and the god awful bloom lighting. dc version actually looks better and is a much better experience.
But you're forgetting that this is Shen Mue, so you're basically comparing shit to poo.
spoiler (click to show/hide)
Just kidding.