Larry Summers is the same guy who with Bob Rubin that got deregulation basically eliminated so that the banks went nuts with leverage. He is not anti QE - he is pro bank and anti regulation so you better believe that if the banks want QE (and they do!), he is not the guy to end it.
summers is widely regarded as a hawk throughout his entire public work. While he may be in the banks pockets regarding regulation the chairmanship will turn decidedly more hawkish with summers in charge.
This is the exact correct move to make to carry out the Taper through the end of 2013 and 2014.
Bernnake starts it, Summers guides it.
This is not a bullish appointment for the mkts, I am sure it will be spun as such