Don't banks fill an important role by allowing people to take out loans and so increasing people's capacity to invest in their businesses, buy houses, etc? How will Bitcoin replace that role if there's no third-party to store people's money, deal out loans and charge and distribute interest?
I'm sure this has already been covered somewhere but I haven't come across the answer yet.
The difference is that there is no "lender of last resort". So the banks are on their own. The government does not have the means to insure deposits, so that would have to be private, if needed.