I've played this game solidly the since last night, and I must say i'm immensely impressed. This version seems a lot more polished compared to Ouendan, except that the difficulty balance tends to be skewed, and the game suffers from irregular slowdown/speedups, ever so subtle, but they mess the timing of the circle tapping, although this could also be attributed to running the game from a flashcard...
I've only just realised that completing the game and unlocking everything is only half the fun...It seems like the Multiplayer mode has all new stories to all the songs in the game! I tried out a single-card multiplayer with YMCA, and there is a story of a 3 on 3 basketball match, and kids fighting over who gets the court...I love it...
It might not have the natural flow/progression of Ouendan, but it's well polished up, and shines further at the more difficult levels, esp EBD! Also the animations of the Agents dancing are brilliant, especially when they do the actual YMCA moves lol, they also have unique dancing on a few other stages...
By the way, has anyone managed to unlock Survivor - Destiny's Child? I can't seem to get it yet :-/