First off so that you know I aint filling you with bullshit, I do own Crackdown 2 and have had it since yesterday, thats a week early.
http://twitpic.com/21st4r
Anyway, if you are thinking of getting it then I suggest you do. I cannot say much because Microsoft have told me not to but I will say that the Demo is crap and does not allow you to fully experience the game.