The thread begun (in the AER) by Paul Romer, as I’ve commented, is deep in links on his site and elsewhere. Here’s a brief take from Krugman, with more links.
Trash Talk and the Macroeconomic Divide – lots of links
Freshwater’s Wrong Turn (Wonkish) – including those freshwater folks he feels don’t fall prey to Romer’s critique
This is a productive exercise, and one that our economic science needs to pursue.