I've been playing this game non-stop for the past few days and after logging serious time with the game, Mass Effect and Bioshock are slowly getting bumped down the GoTY list while Rock Band shoots up like a rocket.
IMO, this is the greatest party game of all time and when combined with DLC, it has the potential to be played for years on end (or whenever the sequel hits shelves). It even surpasses my former favorite party game, Wii Sports. It's that much fun.
Drums are incredible (just wait 'til Enter Sandman, you go apeshit while playing it), singing is surprisingly fun (even with my Gilbert Godfreid singing voice), and guitar/bass is like Guitar Hero turned to 11. Combine all of it into one four-player jam fest and you'll hear more hooting and howling over the game than any other game you'll play.
Now I just need to unlock Ballroom Blitz so I can complete my world domination of the drum machine... I already sang Fear the Reaper so that dream is taken care of... Nothing cracks up a bunch of people playing like screaming at your wife "MORE COWBELL!" in the middle of the song because she's not tapping the mic enough.
I never thought a "casual" game like this would ever come close to GoTY for me.
Anyway, what are some of the thoughts of other Rock Band owners here? Are you playing multiplayer a lot? Single player? Drums? Guitar? Singing?

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