Note that this isn't a "crap-out-a-game-make-a-mil"; he was working on this game for, I believe, 5-ish years.
(worth buying and playing, btw)
Microsoft only takes more than 30% if you are lucky enough to have your game featured (read: you'll make it all back and more in volume).
Disclaimer: I work on Game Studio and the XNA Framework
Note that this isn't a "crap-out-a-game-make-a-mil"; he was working on this game for, I believe, 5-ish years.
(worth buying and playing, btw)