These threads are a mess already. I have to be honest Gaga, Rihanna is really improving as a dancer though, she needs to keep it up and improving she can't come back from this.
GaGa for now because GaGa's choreography incorporates more body movement....right now Rihanna is just working with her legs+waste/cooch...which is FINE. If Rihanna keeps working at it though, she can surpass GaGa in the long run.