Ah, you're entirely right. I didn't misremember--I read his blog rather religiously. I just apparently wasn't quite awake when I wrote what he was betting on.

I should also clarify that he didn't have anyone matching even a lesser amount in the case that the paper was indeed unsuccessful (which it appears to be as it stands, but Aaronson's bet gives it a while to correct problems). His goal, which didn't exactly work, was to get people to stop asking him about the paper. I say it didn't work, because he probably got even more people commenting on the bet, and still a large number asking about the paper.