I don't understand this sentiment - the allure of Bitcoin isn't that it is always decentralized, it's that it can be if you want it to. You decide the level of trust you want to have. If you trust almost no one, you run a full Bitcoin client connected to a few trusted nodes. A step up from that, you're running a chain-less client that has to trust wherever it gets it's balances from. Continue up the ladder until you reach whatever Bitcoin will eventually call banks.
+100 Thank you elggawf! I don't know why it's so hard for people to understand that crucial point! Bitcoin's prime strength is that it is decentralized by default, but naturally (and thankfully) businesses will be created around which Bitcoin coagulates. This does not diminish the decentralized nature of Bitcoin, because there is never a point where one MUST surrender control to a centralized entity. This distinction is crucial.
Long-term, there will absolutely be Bitcoin banks with user accounts. Every Bitcoin user gets to set his own risk/convenience threshold and act accordingly.