Guitar hero 3 is without a doubt the best game in the Guitar Hero franchise.
The game is just like anything Guitar Hero game, you pick a certain character you play many different songs in order to advance to the next set of songs. But this Guitar Hero contains alot of new things to make the third game better than the other ones.
The game actually has a story and the story is that a group of guys are starting a band and they need a lead guitar, you see the flyer and you come to the bands grange and impress them with your guitar skills, The game in my opinion has the best soundtrack, it has many songs like Before I Forget By Slipknot, Rock And Roll All Night By Kiss, Schools Out By Alice Cooper, and many other great songs by great bands. There is also bonus tracks which you have to buy them from the guitar shop along with a few other items and you can download songs which is sadly available only for the PS3 and Xbox 360 version.
You also get involved with guitar battles aka boss battles. I think thats what makes this game interesting because the first and second didn't have it, You battle Slash, Tom Morello, and Lou aka The Devil and instead of star power you get power ups which help you make the person you battle lose. Some of the power ups are Amp Overload, Double Notes, and Broken Strings. There is also battle mode which plays the same as the boss battles.
Now if you plan on playing the game on Expert the only word I have to say is good luck because this game is really difficult on expert, Guitar Hero 1 and 2 on expert was hard but not difficult. There are some songs that are easy to complete on expert but overall its pretty much difficult and get ready for your hands to hurt to because thats going to be happening when you play on expert.
If you guys don't know Neversoft has taken over the Guitar Hero franchise in 2007 and did really good on it. The PS2 was developed by Budcat Creations which they did a really good job it, I just really wish they had on online play on the PS2, Overall Guitar Hero 3 is an awesome game, if your a guitar hero fan and if you don't have this game try and find it because this game awesome.