Oh, my own odds are lower than mattnewport's, just not low enough to call his estimate crazy.

Also, my bid-ask spread is pretty high if we're talking actual bets. I'd take the "yes" side at something like 10:1 odds, and the "no" side at 2:1 odds the other way. And I'd only feel morally comfortable betting the "yes" side in the context of a formal prediction market, where the positive externalities to having accurate odds would assuage my guilt about collecting in that case.