The game will be entered in the Microsoft Dream Build Play competition in June before being released for sale. Currently the game is almost done, requiring only more levels and a little more art and sound effects to be made.
What it desperately needs is play testers, so if you have an App Hub membership, head on over to the App Hub and download it! I will be working on a PC demo soon so that anyone can provide feedback, but until then, it's XBLIG only.