Wow, I just listened to the album in a quiet environment and I have to take back what I said about the production being good. There is genuinely major distortion and clipping on this cd - apparantly there is huge outcry about the engineers boosting the levels to clipping point before it was mastered which made the problem worse. The word is that it can't be fixed by remastering, the only way around it is a full remix and that ain't going to happen. Weird that it could happen with such a big album with such a massive studio and budget behind it... Appartantly the tracks on Guitar Hero sound the way they should (pre-mastering/pre-limiting) and they are way better.
Check this out to hear the difference between Guitar Hero and the cd, pretty awfull... http://www.roadrunnerrecords.com/blabbermouth.net/news.aspx?mode=Article&newsitemID=105530