With sequels, reviewers tend to be biased towards revolutionary rather than evolutionary feelings that if you're plunking down 60 bucks for a game, it should do more than just improve upon the last outing. Rock Band 2 falls squarely into the evolutionary category, however it's the kind of evolution that turns a stallion into a flame shrouded Pegasus with a horn made from pure awesome. On paper, the new features of the game may not seem like much, but the resulting effort makes it one of the greatest music games available today and destroys any need, or desire, to play the original.

The two biggest additions exist on opposite ends of the spectrum, but are equally as impressive. On the one end is the ability to tackle the World Tour mode solo. That's right, no longer do you need to ask random strangers to come to your house and play with your microphone, or try and play bass and sing at the same time, Kip Winger style, just so you can pretend to live in a van with three other people surviving on nothing but Cheetos and simmering resentment. If you like the illusion of being in a band, or you just don't want scary, spiky-haird Goth guy showing up to sing, you can create characters to act as permanent stand-ins for every instrument you're not playing at the moment. Not only does it give you some variety when choosing who to emulate on stage, but it goes a long way to making you feel like you're in a real band.

Other than rocking the solo tip, the World Tour mode is unchanged. You'll travel from city to city, venue to venue, seeing millions of faces and rocking them all. As you rise in fame, measured by the number of stars and fans you've accumulated you'll get access to more venues and more complicated means of transportation as well as the ability to hire staff members and other hanger-ons who just want to bask in your glory. The tour culminates in your band being inducted into the Rock and Roll Hall of Fame and the ability to play the endless set list, a grueling marathon of every song in the game, back to back.

On the other end of the spectrum is the ability to play every mode of the game with other players via Xbox Live. Need a bass player to round out your power trio or you have a challenge to beat that requires at least two players? Simply pop off a game invite and soon you'll be rocking out with your co-rockers. The best thing that can be said about this mode is that there is no discernible difference between having someone in your band via multiplayer and having someone standing next to you, other than the lack of Cheeto dust on your guitar. You see their character, their note chart, when they deploy overdrive, when they screw up, everything. It is seamless and it is awesome. The usual score duels and tug of war competitive modes are still present in local and Live flavors and they're certainly fun for a diversion, but why fight when you can rock?

To further the encouragement of group rocking, Harmonix has loosened the reigns of the World Tour which means band leaders are no longer tied to a particular instrument. If you're playing guitar but realize you don't have the chops for the next song, simply switch out your instrument at the band member selection screen and let Little Hendrix from your Friends list take over while you tackle vocals or drums. Unfortunately, if you're looking to change instruments to get instrument specific achievements, the process of switching instruments so that your GamerTag is currently active for the new instrument is a bit of a pain, however if you're switching instruments simply for achievements, most likely this is the least you've ever done when chasing the score dragon.