Brad Delong and Scott Sumner, "Fed Up"

In a Reason magazine article entitled Fed Up, Brian Doherty writes:

The Berkeley economist Brad DeLong, a popular blogger and former Clinton Treasury Department official who once dismissed Mises’ general monetary theory as “batshit insane,” still told this story in the October 2008 issue of the liberal American Prospect: “The current financial crisis has its roots in Greenspan’s decision to keep interest rates very low in 2002 and 2003 to head off the danger of a deflation-induced double-dip recession.…Six months ago, I would have said that his judgment was probably correct. Today… I can no longer state that Greenspan made the right calls with respect to the level of interest rates and the housing bubble in the 2000s.”
[...]
Scott Sumner, a monetary economist at Bentley University who writes the much-cited blog The Money Illusion, thinks the Federal Reserve was and is too tight with interest rates and money for optimal economic performance. “As everyone knows by now,” Sumner complained in June, “the once kooky and discredited Austrian business cycle model has now become conventional wisdom.”

Interesting. What do you think?