"Rock Band" allows up to four gamers to form a virtual band, thrashing and singing along to songs with friends online or in-person on various phony instruments. The second edition will feature a playlist of over 80 songs - all master recordings - which will include more female-fronted bands and artists who have never contributed tunes to a music game.

If you've already downloaded a song for the original "Rock Band" - at about $1.99 per track, which can't be transferred to an MP3 player - it will immediately be loaded into your "Rock Band 2" song list without needing to be repurchased or re-downloaded. It's the first time such retroactive compatibility has been introduced in a music game.

All prior versions of "Rock Band" instruments, as well as many from the competing "Guitar Hero" franchise, will also be compatible with "Rock Band 2." Harmonix will unleash a collection of new instrument-shaped controllers, including a sturdier drum kit and a Fender Stratocaster reproduction guitar lined with faux wood-grain buttons.

MTV Games and Harmonix are releasing 12 "Rock Band" songs on July 15 from The Who - ranging from "My Generation" to "Who Are You" - that all utilize the band's master recordings. The tracks will be available for $1.99 individually or $19.99 together. The special release coincides with the upcoming "VH1 Rock Honors" ceremony commemorating The Who.