What happened with mtgox is like Enron, it's not an isolated incident, it's actually widespread.

Btc-e.com is another exchange that is running fractional reserve, and ready to disappear with everyone's money at a moments notice.

Without an independent group of auditors, how do you know that bitstamp and blockchain.info aren't running thousand bitcoin deficits due to theft, loss, incompetence, etc?

You don't.

Until a bitcoin exchange/business passes an audit by an outside/independent body (and continues to do so at regular intervals), why should we assume anything but that this business is insolvent, running fractional reserve, or misappropriating funds in some other way?

Oh wait, we should just believe the business and take it at it's word.

Wallstreet has this type of problem even with tons of regulation and government bodies watching.

With bitcoin having none of this, it will certainly be even more widespread.

I'm not saying that government is the answer, but some sort of independent 3rd party bitcoin auditing service that will certify an exchange/bank as 100% solvent and not running fractional reserve is definitely needed.