Some aspects of it are cool, but this is gonna be the first main Guitar Hero I will pass on (I even bought 2 on both PS2 and 360). I already have enough plastic instruments in my room already and I still haven't had my fill with Rock Band just yet, so that can last me until Rock Band 2, which hopefully isn't out for another year or two.
The best part about this game is the defense squad (actually, maybe just soldier) you see around.