This is the best music game that's come out so far. You better believe it. Now, my reasons for why Guitar Hero is soulless, factory-produced crap would take up too much space here, so I'll skip to the conclusion that, before this, Rock Band 2 was the dominating music game, in my mind. The reasons for my liking it so much were polish, support from the developers, depth and realism. Now, with this game, I can add one more to that list: style. Everything in this game is beautiful and unique, in a ridiculously cool 60s psychedelic way.
What really stands out, though, are the dreamscape sequences that play behind the interface on songs that were never performed live. They are magical and ridiculously cool to see, and their polish is immediately apparent. The first song to use this is Yellow Submarine, and although it starts out in the Abbey Road studio, the surrounding slowly changes, until eventually bubbles float up and the band find themselves underwater.
Then, you've got all the bonuses (and there are lots of them) which are really interesting to watch, even if you don't know much about the Beatles (as did I, before playing this game). And that leads me to the reason I thought this was worth purchasing despite also owning 3 other rhythm games: this is the perfect way to get introduced to the Beatles, and that, alone, is worth more than 60$. Although I'd tried to before, I'd never really "gotten" what the band was about. Spend an hour or two playing this game, however, and you'll get it right away, and I love it.
In a sentence:
Incredibly polished, unique and complete; this is a great game not just for Beatles fans, but for the uninitiated that want to see what all the hubbub is about.