Every season there is someone to hate, thankfully, because otherwise watching would be boring.
All time, though, I'd say my most hated would be JFP for male and Jenna M. for female. He was just obnoxious and thought he was cool, which made me hate him soooo much. And JM thought she actually deserved to win, when Survivor fans know she really managed to win by default.
I'm going out on a limb here, and please don't throw anything at me, but I'm thinking Shane is pretty darn funny. So far, he's been the most enteraining castaway this year.