Beyoncé is good but she never does anything spectacular. So I'd say she is the weakest.
What a shock.
Although GaGa is entertaining, she isn't as good as P!NK or Bee.
Then again, she hasn't been in the game as long.
She has plenty of time to hone her skills.
P!nk is highly choreographed, sometimes that's great, other times it's boring. Glitter in the Air remains her best performance, but she can't keep doing it because we've already seen it. Her vocals are good, but her songs aren't very difficult to sing, not for the other two girls.
Lady Gaga is still way too sloppy to compare to either of them, but she does have the better piano skills and her vocals are decent.
Beyonce's choreos aren't intricate, but they do require some innate talents (rhythm) and they're intense, especially coupled with those vocals. She sings fast, with a lot of words and usually in her mid/high register. Her dancing is big, rhythmic and very fast. Either you can do it, or you can't. I'm pretty sure the other ladies can't.
