The selloff started while USA was asleep, so perhaps it's attempted arbitrage by European users: sell out now, withdraw via SEPA (which is still available from Gox), and rebuy on a different exchange in a week or two?  Under the circumstances, new fiat is unlikely to be deposited at Gox, so price won't go up, except perhaps for impatient Americans.  Today's the day we learn who is playing with money they can't afford to lose.