I don't want to upset any big fans here...
But it has to be said. This is an average animation with an addictive song. Nothing special, and certainly nothing new. I liked, I'm not denying that, but when you pull it apart, you see that it's just another musical, with an ageing yet amusing theme. The comedy is predominantly slapstick (and hardly laugh out loud), and the animation is quite lazy. It also has a tremendous amount of potential which has not been done justice.
Overall, this still is a good piece of flash, and somehow offers a mature take on the humor, but is still bereft of originality and real talent. As for the music, it is well written, but given enough time, many people could come up with something just as good. This is good, not great; and certainly not #1.