I'm definitely willing to put $300 to $100 on Riemann not being proved - even knowing that you may have some relevant insider knowledge.
I guess one issue is that we couldn't expect to know for sure by this time next year if it had been proved or not - I'd be willing to go with something like "by January 1 2012, no preprint will exist of an essentially correct proof of the Riemann Hypothesis (in ZFC)".
Yeah, multiple people have called me out on RH, and thinking about it more, I'm probably was just being way too underconfident.
As we did last year, use this thread to make predictions for the next year and next decade, with probabilities attached when practical.
Happy New Year, Less Wrong!