While I'm sold conceptually on cryptocurrency and I firmly believe it's here to stay in one form or another, the UX has a very long way to go before any amount of mass adoption will occur, IMHO. One thing that really irks me is that, due to the current price in say USD per BTC, user's are forced to deal with fractional notation to conduct standard transactions. The average person is not going to easily grasp the concept of Bitcoin fractional units. And this is compounded by the fact that block-chain transactions are non-reversible "push" transactions, thus the consequences of mistakes are solely the responsibility of the user. Still, I believe the open-source communities and cottage industry springing up around cryptocurrency will no doubt solve these issues!!!