EDIT: Update on this story here

The latest issue of the GamesTM Magazine (issue 69) has a two page article discussing the PC / Steam smash hit Audiosurf - a game which allows a player to 'race' along psychedelic courses made entirely out of the song itself while connecting blocks coming down the line - and you can plug in any MP3 file you like to create a new level!

At the very end of the article, it mentions that it will be coming "soon to the Xbox Live Arcade."! Can't wait!

Source: GamesTM Magazine issue #69. Thanks to Gowans007 for the scan.