the most interesting part I think is that he was actually able to withdraw 643.27 bitcoins (much more than usual daily limit) when they were for around $1.55 each which means withdrawal limit for BTC was calculated at current market prices.
If this is all true, then hacker is probably banging his head against the wall now because he was likely able to steal millions without any hope being ever caught. or did he?
MtGox claims he got away with only $1,000 worth of bitcoins however if he took them out of the exchange right after the crash when their market value was around $0.01... oh well, there is something very fishy going on here. I suspect MtGox doesn't have enough bitcoins to back their accounts now. If you see in upcoming days people complaining about MtGox not willing to physically transfer bitcoins back to their traders, it will be more than obvious.