Bitcoin throws challenges to bank as bitcoin is peer to peer network. But if in future bank will not work with bitcoin, there will be a lot of problem for them. So I think if bank work with bitcoin, it will be good for them as well.
There is a problem that must be harmonized if bitcoin is connected to the bank. First, the bitcoin peer-to-peer transaction is different from the bank which is the regulator between the sender and the recipient. Second, bitcoin doesn't know holidays, while banks have holidays. Then, bitcoin is anonymous while banks must have an identity. But this is not a difficult thing to synchronize, the most important thing is that the government must accept bitcoin and make regulations so that bitcoin owners feel safe when their identity is known.