While I know this is a joke thread, I wouldn't be too surprised to find out that Nintendo was working with a camera (of some sort) for their next system but I doubt there approach would be exactly like Sony or Microsoft ...
One thing I think is a possibility is combining low cost projectors and cameras to have the game enter into the player's environment and not remain confined to the television; the reason I see this as a possibility is that very small, low resolution projectors and cameras are getting to a price level where they could be sold as an inexpensive add-on or included with the release of a system for not too much money. In an ideal set-up you would want 3 or more projector camera pairs to be able to project an image on a surface which had minimal impact from a user's shadow, but 2 would be adequate in many/most situations, and a single pairing would still be of some use.
Now I should note that the resolution of these projectors would (probably) be below standard definition TV (480x320 or possibly 320x240), and the frame-rate would (probably) be fairly slow (24hz or 30hz), so it wouldn't be all that good for rendering complex 3D images; but if you wanted to generate a play surface (like a DDR mat or whatnot) or something like a heads-up-display or world map it could do a fairly decent job.
But, this is just a theory of mine, and Nintendo is probably going in a completely different direction
