I don't think that it will disappear banks as banks are already have much works to do and their work is not only to store money for people but they are also maintaining the financial affairs for governments and for different organizations.
The bank's tie with the government is the one that keeps it surviving and not just the money... That is why it will be difficult for bitcoin to make banks disappear, bitcoin could only substitute the money but not the other transactions that banks are holding...
but i think bitcoin can disappear banks, but in one condition, if all the people of the world start using bitcoin and stop using fiat currency,and then banks will automatically disappear, but i think it is not possible in present time it will tame decades as most of the people still do not know any thing about bitcoin.
I do not think it's possible at all to bitcoin destroyed banks. The fact that it is better to cooperate than to conflict. Perhaps it is superfluous thoughts of users who want to bitcoin took the lead.