Callum, Mace and Clanger are all right in their differents ways. There's definately a difference as to what R&B is played at difference venues all over the country, almost a north -south divide! Most mod nights in and around London tend to play a number of genres, including R&B, Club Soul, Ska, Funk, Latin, Hammond etc, although there has been a move towards more fifties style R&B and Popcorn at some nights, it really depends which DJ's are spinning.
There's also a big difference in what is the perception of 'R&B' in northern and mod circles. I often see records advertised as the next 'big' R&B sound on a list (some on this site) and it's not a style or sound that's currently popular, it's just the seller trying to move some unwanted stock. It tends to be only the big mod scene tunes that crossover to the northern scene, most tunes played in some venues would never be played out in northern clubs, especially some of the latin, hammond and funk style tunes.