I'll preface this by saying that I have, in fact, NEVER played any Guitar Hero game. The idea of it has never really interested me at all.
We're now on the third installment into this series of games, and I still don't get the appeal. Its always made me think of Dance Dance Revolution. Only, rather than jumping around on some squares like an idiot, you stand there pushing buttons on a toy guitar. Yet, I see people raving about it on message boards, I hear people talking about it at work, and South Park even dedicated an episode to it (funny episode, by the way).
Now, I'm not exactly a huge fan of music. I listen to it in the car, and I use my mp3 player a couple times a month. Other than that, I pretty much don't have music on. Music doesn't factor into my opinion of a game, unless its so completely annoying that I simply can't tune it out. I barely notice music in movies and television. I suppose this is probably a large part of my attitude towards this game. I don't value music much, so why would I enjoy a game that centers around it?
I really don't know. Maybe there's something that I'm missing here. Fill me in if you know something I don't.