I can see you put a LOT of work into this!
Graphics: I'm not so much into the South Park art style, but the animation itself was AWESOME. Many great moments with both nicely-made tween AND frame-by-frame animations.
Style: Again, not into the South Park style really, but that was the only thing I didn't fully enjoy about it.
Sound: Since it's only one song, that's all there is to judge, but it IS a good song of course.
Violence: Average amount, but ranking high on that doesn't really make much of a difference to me.
Interactivity: The secret clip idea was brilliant. I don't think I've ever seen any other flash movie do something like this!
Humor: Lots of cute little suttleties hidden around the movie. I didn't laugh out loud or anything, but I appreciated the humor nonetheless.
Overall: GREAT stuff. This movie definitely deserves its spot among the best movies on Newgrounds.