There is regulation against theft( though does any legal authority investigate bitcoin thefts?) . I meant regulations dealing what bitcoin exchanges can do with your money or what steps they have to take to protect it. For example, although I don't think any bitcoin exchanges loan out money yet, if they did, there is no amount they are required to keep as a minimum balance to cover withdrawals (unless the government legally deems them a bank, in which case my entire post is irrelevant)