Of course I think Bitcoin is a threat to banks and that is one of the reasons why the government have not regulated these digital coins too. But I also doubt banks would disappear just because people will be drawing their attention more to these digital coins than paper money. There are still a lot of people in the world who thinks Bitcoin and other cryptocurrencies will diminish after a few years and stick to what they were used to which is I think understandable. You can't really please everyone because they have their own opinions regarding the digital currencies.