so people only have to buy the camera instead of a move type of device and the camera?
I think the only thing the light on the controller is good for is position of the controller to make player switching automatic if you have the camera, + color changes depending on what is going on in game (game specific, camera not required). It really isn't a big feature of the controller, just a bit of extra functionality.
so for motion games, you're gonna need move controllers.