Video is low quality, unconfirmed source...
http://gizmodo.com/5436510/leak-half+life-2-playing-on-project-natal
From the same party that brought us Geometry Wars on Project Natal, here's a clip of the Microsoft's upcoming motion system handling Half Life 2—the first time anyone's seen Natal playing an FPS.
We should mention, the clip comes from an unconfirmed source, but everything about the system is reminiscent to Natal to us—we should say, Natal running a title in early beta. The control scheme seems simultaneously intuitive and awkward in what we're assuming is a proof-of-concept, the user repositioning their view by moving the screen with their hand.
Still, while the verdict may be out on how well Natal will handle first person shooters, it's pretty darn cool to see a player control a complex game without a controller between them and the screen. And if you were playing an FPS involving the manipulation of a variety of objects beyond mere guns (imagine grabbing a key, crowbar or, heck, even a flower) what's now just a novelty could become something much more compelling.