Russ Roberts interviews Scott Sumner in the latest EconTalk podcast. Roberts seems open to Sumner's ideas, which makes me wonder how he reconciles them with his earlier skepticism about there being insufficient aggregate demand. Should Roberts need any more evidence on the importance of nominal income (i.e. aggregate demand) shortages in explaining the ongoing slumps in the United States and the Europe, he should check out this post and this one.
P.S. Russ Roberts' recent interview with Alex Tabarrok on innovation was really good too.