There is a slight difference. There is definetly a major difference between R&B and Rap. Rap is more fast paced, R&B tends to be generally slower, easy going. On a side note, R&B and Hip Hop often gets grouped together.
Since it's the only thing I like up there; Rock. Rock and metal is practically all I listen to. Metallica, SOAD, Dimmu Borgir, Adema, Dragonforce, Lordi, In Flames, etc :]
Hardcore metal all the way. I actually just went to see Trivium last night with Celladoor, Protest the Hero, and The Sword.
I like all musics Rap, R&B, Hip Hop, pop, Dance, rock, hard rock... and a lot more I have no favorite.