At least for me, bitcoin have not move money after shutdown.
I have sent money three times to three different addresses to mybitcoin.com before it was down. (All three transactions were made 2011-7-29 between 4:00 and 20:00 UTC).
No money from these addresses was touched since then (according to https://blockexplorer.com/ as of 07-31 02:04 UTC). Can anyone who send money to mybitcoin check if they touched you money after they went down. Also if you received money form them recently, then you can also try to guess their addresses: when you get money they combine moneys from several their addresses, and give to you (and probably to some other customers) and then return the rest of the money to their new address. So if the transaction has two out addresses than you can be  almost sure that one that is not yours is theirs. You can check if any money was spent from this address.   
So do they move your money?