throughout the last week immediately after the first press release of mtgox regarding halted btc withdrawals, you could observe huge rhythmic btc dumps @mtgox every 2-5 minutes following always the same pattern ("the whale of mtgox"). the sum of these dumps up to now is approx 140000 btc at an average price of around us$270. ie a us$38 mio sell-off. there were a few stuck levels eg at us$261.24 yesterday and us$148.15 the day before yesterday. these were manipulated levels by the whale serving all asks above these levels every 2-5 minutes. this is very difficult to do through the api of mtgox. but very easy if you're in charge of the order book itself.