I would just like to write on the other side of things, cause the review here helped me buy the game for a present and after playing it, I am thoroughly disappointed.
I would just like to state that I played it one night, 3 games, 2 players. First of all, I have a wealth of music knowledge, I have some 18,000 songs on my iPod, and I only knew about 3/4 of the songs. Strange Andy Williams songs, Boney M, Pet Shop Boys songs I've never heard of, aren't exactly songs people know words to (And I know some Williams and Pet Shop Boy songs). But, that's fine, that makes the game a little more challenging I suppose. The other problem was during the second game, we started getting repeats, same song, same part of it to guess. Then by the third game I occasionally had to skip about 4 songs to get to a new one (which isn't easy to skip, you are forced to watch the song and Fatone's response). And the last thing I didn't like is that half the game, you have to put your back to the TV to come up with the missing lyrics. It'd be better off just letting you sing the first part of the song and then putting blanks where you are supposed to guess the part of the song. It's hard listening to their horrible singers and what they're actually singing. I'd rather sing along and then guess when needed, they could show the answer after that on the screen. This also leads to making it impossible for someone to play by themself, for the answer will be on the screen before you can turn away and guess it. Annoying.
Now, I'm not saying it isn't fun, it is. But I think if they spent a little more time on a DVD game, that is basically just a DVD, then they could help us out and add a little more production value into it, and more SONGS.