Bitcoin is supposed to work without the need for a trusted third party. If that were true, we wouldn't be here discussing MK's evil deeds.
Bitcoin works fine without a trusted third party.
Bitcoin users who refrained from trusting any third parties lost exactly zero bitcoins.
Bitcoin promises to let your "be your own bank". If you decide to be your own daytrader then you're on your own.
I agree. However it's a fact that an inordinately large number of people chose to entrust their bitcoins to an unreliable third party such as Mt.Gox. The resulting disaster and those that may follow along the same lines can be tackled either
a) by pointing out , not without reason, that this is a non-issue, since in the bitcoin world it's every man for himself. That's fine , but it may scare off the naive adopter, i.e. the vast majority of people, compromising bitcoin's success.
or
b) by introducing regulation for exchanges, i.e. turning them into banks, transforming the current bitcoin model into something quite different.