Lol how can Britney even be called a dancer especially nowadays. I laughed the last time I saw a clip of her 'dancing'.
The only two on your list that can be called dancers are Janet Jackson and Madonna. Beyonce has this jerky thing she does when she dances nowadays, with a few hip rolls, and butt shaking thrown in. The others move their arms, step around a bit doing a few simple choreographed moves. Most of the dancing is done by the backup dancers who dance better than the singers 90% of the time. So, my choice goes to Janet Jackson. Just go watch her video with her brother titled "Scream." You'll see why shes a dancer, also go look at some of her lives.
