ARNOLD KLING
August 14, 2011
The Top Political Contributors
August 11, 2011
Gender and the New Commanding Heights
August 11, 2011
Jamie Galbraith Makes an Assumption
August 11, 2011
Macroeconometrics: The Science of Hubris
August 10, 2011
Real and Nominal Bond Yields
BRYAN CAPLAN
August 14, 2011
The Effect of Thumb Sucking on Income
August 12, 2011
The Voice of Cold, Hard Truth to All Would-Be Educators
August 12, 2011
Ability, Morality, and Prosperity: A Paper and a Report
August 11, 2011
The Theory of Time and Frittering
August 10, 2011
Male Variance and the Remnants of the Gender Gap
DAVID HENDERSON
August 9, 2011
Hayek in "Unbroken", Part Two
August 8, 2011
Hayek in "Unbroken"
August 5, 2011
James Bovard on the Peace Corps
August 4, 2011
Summers Way Off on FDR and 1941
August 3, 2011
The "Amazon" Tax


No idea either, but there are feeds for individual NBER programs.
And the link to the feed for all new working papers isn't on the page itself, naturally: you have to view the page's metadata or look in your browser's detected list of such feeds.
It's rather odd, really. Perhaps it's a work-in-progress and Google's spider just picked it up early.
Sounds like an answer to "You might be an econ geek if..."
Many thanks, Arnold! Very cool.
new.xml seems to be an aggregate of all the individual feeds
The feeds aren't new, but as david suggests appear to be a work in progress, as they aren't advertised and only recently are a lot of papers added.