Wow I actually agree with Tierra for once.... very spot on. This is a pop forum so I wouldn't expect people to truly understand what R&B is. They always throwing it around so loosely. Pop is a legitimate genre, they wouldn't have Best Pop this and that at award shows if it was made up.
BTW, Usher is R&B.... go listen to his albums and its clear as day. Robin Thicke is R&B as well but he used to be pop/rock if you ever heard his debut album.