We can work with regulators to make sure Bitcoin is acceptable to them. For instance we can ensure that it remains possible to track the flow of money through Bitcoin. We can also ensure that there are options if certain funds need to be frozen and blacklisted, due to fraud, theft, or because they encode illegal data. We can work with them to find ways to apply AML rules to Bitcoin transactions and to the exchanges. There are ways to put taxation into Bitcoin itself, so that taxes are automatically applied when a transaction is made. Maybe even one day we'll be required to prevent dangerous levels of deflation. A lot of these changes are technical, such as improving scalability so transactions can remain on the blockchain, developing P2P blacklist technologies, and preventing deflation.