It all depends on your choosing, whenever you like the flexibility of having control of your own money, or to have the ability to earn interest from your savings account, I would like to state that each has their advantages and disadvantages. So until Bitcoin becomes a mainstream currency, it is best to use both a bank account and a Bitcoin wallet. Just my opinion. 
there are advantages and disadvantages of both, the best is use bothI like the bank because there is interest
You can always earn interest on your Bitcoin savings by various ways like Magnr, or Poloniex lending (which earns you interest). Isn't that similar to a bank as well, in earning interest? Just expressing my thoughts by the way. It is good to have both (BTC and Bank) in the meantime.