Romance continues to blossom between Jessica Simpson and John Mayer. Simpson was spotted grooving at Mayer's Miami concert on Friday night, dancing for the entire set as well as the 20-minute encore. "She was rocking out the whole time," said a witness. "She only seemed to know the words to his older songs though, because she sang along to Your Body is a Wonderland and his older hits." Simpson was joined by BFF Ken Paves as well as Billy Joel and his wife. "She was dancing like she was a real fan, and a lot of the crowd had their eyes on her the whole time," said the concertgoer.source