Why Quantitative Easing Hasn't Caused HyperInflation
I think that most of the arguments that Higgs made are correct. The most important factor is that the increase in the monetary base hasn't increased money supply very much. And the monetary base is irrelevant for price inflation except to the extent it changes money supply.
There are several reasons why it has had only a limited effect on money supply, including the two that Higgs mentions, that interest that the Fed pays on bank reserves now unlike before (that interest payment BTW makes no sense at all given the Fed's pro-inflationary policies otherwise, unless you assume that the Fed's purpose is to maximize bank profits), and the fact that banks are more reluctant to lend. Another factor that Higg didn't mention is that households and companies are probably also more reluctant to borrow.
Another factor that Higgs overlooks is that the reduction in real interest rates has increased money demand, and as higher money demand has a similar effect as a lower money supply, this has limited the effect of the money supply increase that has in fact taken place.
I disagree with Higgs that it will inevitably lead to hyperinflation or even greatly accelerating rate of price inflation. It would eventually, if the Fed didn't reverse their asset purchases once banks becomes less reluctant to lend and households and companies becomes less reluctant to borrow, but since that would likely be associated with a real recovery as well as higher price inflation, the Fed will be able and likely to reverse them at that point.