I've had a pretty busy weekend, so I didn't have much time to delve into Rock Band 2, and looking over my schedule for the next week or two, chances are slim I'll be up to unlocking anything in the game anytime soon. For those of us with little time or little patience for unlocking new tracks, Harmonix have included a handy little code in game that unlocks everything, all at once. Mind you this will completely strip the joy of discovery out of the game, so use at your own risk.
Simply go into the game modifier screen and enter in the original Rock Band unlock code - Red, Yellow, Blue, Red, Red, Blue, Blue, Red, Yellow, Blue - and poof, you're a joy killer. I tested the code out on my game and it works like gangbusters. Then I stared wistfully at the track listing before putting down the guitar and trudging back to my desk, completely broken.
How To Unlock Every 'Rock Band 2′ Song Right Away [MTV Multiplayer]