Second, the critical aspect making 2008 so bad was the contagion effect throughout financial markets - MBS were so pervasive that suddenly no one knew if their bank's assets were worth anything at all. Uncertainty is the worst for financial markets - they tend to assume the worst which can lead to credit just seizing up. That was a trigger for some of the worst of the economic damage. Despite the recent turbulence for banks, the situation isn't comparable. There banks were holding some of the most widely traded assets, generally considered extremely safe - they simply had too long of a time horizon (which is still poor risk management). No one is worrying that the banks' assets might actually be totally worthless and, with the support signals coming from the Fed and FDIC, it's doubtful the crisis of confidence blows up the way 2008 did.