I got Guitar Hero Metallica from Gamefly yesterday. I played though the guitar career and I'm doing drums next, and I noticed one hilarious thing: the guitar "gimmicks" – notes during sustains, tap notes – are detrimental to the gameplay, yet the gimmicks for drums – freeform fills, "sustains" – are beneficial. This is Guitar Hero, tacked on drum gameplay shouldn't be better than the series' main focus.
Oh, and it has Queen, Master of Puppets, Welcome Home Sanitarium, Nothing Else Matters, The Unforgiven, a Thin Lizzy master track (lol Harmonix), etc. Metallifacts and lyrics are pretty boss, too.
Wish Harmonix would release a lot of the Metallica tracks as DLC already, if only so I can enjoy them on guitar. (Well, that and so I can play them after I'm finished with GHM, too.)