Hmmm...
For a collab... this is not fair.
The only animator that I consider good in this flash is Ultimate_TH, IMHO. I really don't know how hard can it be to animate... but considering this was made by several people it could've been better.
Pros:
Every section has a relationship with the BG song.
You used many types of angles and techniques.
Cons (this is the bad part):
Some sections should be removed. No offense intended sweet_kat22, but your section lowered the quality of this compilation.
There are sections in which the characters were drawn preety good, but the background screwed the setting.
There is talent in some artists here. Try harder; it might get better.