Im not sure how MtGox records their prices....
but could i just buy .000001 bitcoins at $100,000/btc and claim that the price hit an all time high?
these bets about future prices seem a little lopsided if that is the case.
why would anyone bet against them, if i could influence the bet in one direction for less money than i would win from the bet?
You'd buy into the lowest offer.