Eh, I don't know. I've always found Beyonce's dances to be .. well .. Ridiculous.
The Put A Ring On It video especially. Ciara does more urban, like you said; pop-lock and whatnot.
I guess it all comes down to what style you like, but personally, to me I find Ciara the better dancer. Ciara - Like a Boy: Well choreographed and clean, well hit moves.