And one more thing
Q: Why mandatory Kinect!? are they SPYING on us!? OMG!
A: Kinect became mandatory because MS wants to see it used to it's full potential by developers. Ie: A horror game that knows when you're relaxed so it freaks you the hell out when you literally least expect it. They invested a lot of time into what is actually a very advanced, underused, and honestly futuristic peripheral. If it is mandatory, developers won't be scared to integrate it into their games and you'll see amazing new things. (Example: The Psycho Mantis fight from MGS1 when dualshock hit the scene, too damn cool back in the day...)