Banks are valnerable there have been a number of major data breaches this year alone with banks its just not as widely reported and consumers have more confidence in system (for good reason)If banks were as vulnerable as the exchanges... the dollars value would never have the current demand.
Hence the creation of the FDIC backing.
Exchanges are the banks to a bitcoin. If the government ever insures digital currency.. then hell.. I'm in.
Until then.. I'll run more tangible stuff with historical trends.