It's called Shmusicup and looks like a good idea. They have an interview with the creators over at Silicon Era (http://www.siliconera.com/2010/11/16/heres-how-shmusicup-works/). I hope they release a better video, because this looks like a great idea, but could be implemented horribly. Would make a nice DLC for Xbox/PS3. It'll make me break out some 140bpm techno :P
Weird. It's like an shootie version of CD Battle.