I'm sorry, but the kinect is going to fail, and fail very very hard. Furthermore, while I know consoles do have quite a strong FPS following, saying hardly anyone plays FPSes on the PC anymore is the most ignorant statement I've heard in my life.
Even if you went by the Steam-only numbers, you'll see that there's tens of thousands, hundreds of thousands...nay, MILLIONS of gamers playing with key+mouse.
Also, considering that kinect isn't even OUT YET, where does this guy get any validity?
He also looks like an idiot. Also, Strike911 is right.