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If Ms lets developers use it as an add-on to the standard controller it can be great to enhance immersion. Add simple headtracking to an fps, not the kind where you rotate your head, but where the view is adjusted according to the position of your head, to simulate you looking through a window. Useful to peak around corners and peer over ledges. Manipulate keypads with your hands and pick up and use certain objects. (while standing still) Fun but not essential.
I don't think it will add much in forza 4. Walking around your car, not interested. Headtracking in racing is a bit off putting, hard to hold the racing line when your viewpoint is shifting. Everytime I look into a corner in GT5 I nearly go off the track :/
I don't think voice recognition is ready yet, but it would be great to actually be able to talk back to characters in mass effect for example.
I'm sure some developers will come up with some very interesting puzzle games for kinect. However I'm afraid the whole you are the controller thing is not going much further then what we have now, you standing in a relatively small area or stuck on rails.
We'll see next christmas. Please let it not all be kinect sports resort, kinectimals 2, dance central 2.
