Ivy. All th top players themselves say Ivy. I love Negraneau, but he isn't as skilled in some of the mixed games as Ivy is. Negraneau has gotten kind of spanked in some of the big cash live series, but I love his game.
In cash, I think it's Ivy and Patrik Antonius.
I played at the same table with Antonius in 2007 at the Aussie Millions for a full day...14 hours. That same table had Marc Karum, Lee Nelson (who won it the year before and wrote the book "Kill Phil Poker" and late Russ Botaright (Hendenmob). It was a ridiculously skilled table and Antonius dominated it like he was playing with school kids. At the time I really kind of hated the guy, but he is actually a super nice guy and it was getting my ass kicked that I hated. (I did manage to limp into the $$...barely)
Now my favorite player is...Antonius. I learned a lot from that beating.