The point is, if Microsoft will need to sell further peripherals in order to show that Kinect can do certain things, what restricts Sony from releasing a more powerful camera to do exactly what Kinect did coupled with their existing motion controls? And how does that differ in any way?
Quite honestly, for Kinect to be 'proven' right or it's detractors to be proven wrong it will have to play games like Call of Duty with no controller or peripherals.
If you need a controller, how again does Kinect differ from the competition or remotely stick to it's controller free gaming shtick? Basically, what this says is that Kinect alone is half of the solution and coupled with motion controllers is the other half of the solution (The solution Sony came up with). Which would lead belief that Sony was correct in it's initial assessment that you can't go the 'Camera-only' route if you want games with depth.
