He is saying that we are in danger of having a double dip recession:

On the current policy path, it would be surprising if growth were rapid enough to reduce unemployment even to 8.5 percent by the end of 2012. A substantial withdrawal of fiscal stimulus will occur when the payroll tax cuts expire at the end of the year. With growth at less than 1 percent in the first half of this year, the economy is effectively at a stall and facing the prospects of shocks from a European financial crisis that is decidedly not under control, spikes in oil prices and declines in business and household confidence. The indicators suggest that the economy has at least a 1-in-3 chance of falling back into recession if nothing new is done to raise demand and spur growth.

Considering Larry Summers’ record, I would put this to a stopped clock being right twice a day, but I agree with him.