Sensitive singer-songwriter and ladies' man John Mayer leaves the Chateau Marmont in LA last night while trying to have 2 separate phone conversations. But, who's on the line? Could he have current gal pal Minka Kelly (of "Friday Night Lights" fame) on one line and former flame Cameron Diaz on the other? It's rumored that John and Cam could be trying to rekindle their relationship. The two were recently spotted together in New York City, looking like more than friends. John, don't try to balance chicks like this, it never worked for Greg Brady, and it probably won't work for you either!