As far as taking one step forward and two steps back goes, Neversoft and Activision have it down to an art. Sad, really.
Metallica is one of my five favorite bands, so this might be biased by a point or two. Can't complain about the soundtrack then can I? This is the first GH game I can say I don't hate a single song. However, there are some BIG omissions. No Exodus? No Black Sabbath? No Echobrain, No Joe Satriani? No Blue Oyster Cult? And even some iconic Metallica songs are missing. (Four Horsemen, Blackened, ...AJFA, Jump In The Fire, Ride The Lightning
Neversoft and company took the GH:WT engine and improved upon it. Well, improved in SOME ways. The HUD while playing is cleaner and better in a few ways. (Moved rock meter, etc...) But some things don't change, like the incredibly BAD vocal engine. I've played through the guitar career on Expert, so I'm mainly telling this from a guitarist's point of view. Ironically, the game is too easy! Not the songs, persay (can only get about 18% through War Ensemble), but the game itself. Someone at Activision said "Hey, let's steal some stuff from the other guy, and have your star progression mark progress!" All good, I guess, but I'm a decent guitarist, so I unlocked and beat "Thing That Should Not Be"-the last song, in about a day and half. It only requires about...70-75 stars to complete the career? And there's a possible total of 290 or so? Geez, couldn't it have at least been a hundred?
And aside from achievements, there's not a lot of substance in the 'content'. Some small pictures, a handful of low quality bootlegs, and some behind the scenes making of crap. No interview with the band, no career retrospective, no awesome videos of them failing their own songs in game. The Rock Star Creator is near pointless with a lack of clothing options and, hell, you only use them for about 40% of the setlist.
Hell, Cliff Burton and Jason Newsted aren't even shown and barely mentioned! I can see why you might leave Dave and Ron out of a mention, but one of the classic members from their first album and someone who was in the band more than ten years don't even get a photo in their crappy photo album? I can see not having them PLAYABLE, but WHERE ARE THE CLIFF BURTON BASS SOLOS?!
In the end, this game suffers the same issue GH: Aerosmith had; lack of replay value and content. Even metalheads would be slightly disappointed at the lack of depth. 7.5 of 10