Xbox has confirmed the 4 gb kinect bundel, and it costs 300 dollars. We'll its pretty expensive, Sony confirmed that Move will be less then 100 dollars. But if you want to buy ONLY the Kinect you can just pay 150 dollars. Its a fine value.
With Sony touting the fact that the PS Move motion-control system will support such titles as SOCOM 4 and Killzone 3, Greenberg also addressed how Kinect will support hardcore gaming. He said that Kinect development kits "were in the hands" of many studios known for core gaming and that the system "had the potential" to be used in conjunction with a controller