My dreams have come true: Metallica as arrived in Guitar Hero. Unfortunately, it got there by way of hackers.
Guitar Hero II: Master of Puppets
I am really not sure just how many copyright laws this violates. Not only is there a copyright on the song, but there is also a copyright in the recording itself. I wonder if any of Guitar Hero's copyrights are violated? It certainly requires modification of existing equipment but it looks like the required programs are free (aside from the mod chip of course). They are definitely making illegal copies, but are the modifications far enough away from the art of the game so as to be deriviative works? Infringement was never so full of rinks and runks.
2/11/07 - in answer to my own question about possible Guitar Hero copyright violations, it appears that there is a previous case holding that created levels for Duke Nukem are like sequels, and an unauthorized sequel is an unauthorized derivative work, i.e. the Duke Nukem makers can stop level creators from distributing copies. Sorry hackers. See Microstar v. FormGen, Inc., 154 F.3d 1107 (9th Cir. 1998).
By the way, there is rumor that Harmonix and Red Octane are putting out a new game that will actually teach the player how to play the guitar, stating, "Once you're done playing with your toys [the current GH guitars], you come see us." Awesome.
Damn, my real dream come true