In a way of the biggest bitcoin exchange "mtgox requires physical identification"...while one of the main points of Bitcoin is total privacy :-/
You guys need to get over this. Seriously. If you want to transact with real world cash, you are going to have to follow real world rules. And one of the main points of Bitcoin is not total privacy, it is pseudo-anonymity. There is a difference, and it's fairly big.
Mt.Gox may have been far from perfect in handling this situation, but it is a growing pain of a totally new economy. It will become easier to convert BTC/USD/other in the future if Bitcoin increases in popularity. You gotta roll with the punches for now and allow Mt.Gox to work better at streamlining this process so other people in the future can benefit from those growing pains.
People also need to understand that the exchanges are not Bitcoin itself. In a peer-to-peer situation Bitcoin can offer pseudo-anonymity - that doesn't mean the exchanges can
legally offer that (and I'm quite sure that none of them want to get shut down for offering it illegally). The exchanges should certainly be offering
privacy, which means only disclosing user information when required to do so by law - AML laws require them to collect that information and privacy laws prevent them from disclosing it without legal cause.