Another article in the NY Post has his wife calling him a sex addict too. I can’t remember for sure, but I could swear there were rumors about him having an affair with Sofia Coppola when they made “Lost in Translation.”
Maybe it depends on whay you mean by "sex addict." I get the feeling Bill would do just about anything if he were drunk or stoned enough, but sex doesn't look to be a driving passion in his life. It's more just part of the party. But what do I know?