I hesitate to weigh in on this. But I must say all this talk about Paul Krugman's alleged conflict of interest over Enron seems ... well, a touch over-wrought?
Is this really a problem? As nearly as I can tell, Krugman got paid $50,000 for serving on some advisory panel for Enron in 1999. For $50,000 he hung out for a couple days at some conference and talked economics. He was supposed to do it twice, but the other conference fell through, or some such thing. (By the way, Krugman has posted his own defense here.)
A few points. One, conflicts of interest usually get attention when it's dog bites man. That is to say, if Krugman were making excuses for Enron. Since he's not, what exactly is the problem?
Second, Andrew Sullivan seems to think that the mania for efficiencies which Krugman displayed in this Enron article in Fortune was somehow wildly out of character. The idea being that Krugman is a taxing-loving lefty economist and that this particular, more Smithian article shows he was on the take, etc.
Sullivan just must not follow centrist or liberal economics that closely. Perhaps a wise bit of inattention, but telling nonetheless.
When I worked at the American Prospect, certain economic journalists at the magazine were endlessly griping about Krugman as some sort of right-leaning or establishment economist. Actually, more than one, come to think of it. There was a even an issue cover I think, or at least some page art we had commissioned, showing Krugman as a crude pitchman or something. I always thought this sort of talk was a bit whacked. But well ... we don't have to get into my history there.
In any case, the relevant point is that the seeming oddity or strikingness of Krugman's views in that article only seems so if you haven't followed the field. And I think the common assumption would be that Krugman -- at least regarding popular economic questions -- has shifted a bit left on a broad front in the last couple years, though I'd probably chalk that up to the terrain shifting as much as anything.
If there's an embarrassment here, it's that Krugman participated in the common business of taking a pretty large sum of money from corporate bigwigs for a pretty small level of exertion. (Note to corporate bigwigs: this is a common business in which TPM is eager to become involved -- though he'll keep criticizing until the offers start coming in.) But I don't see the conflict, since he seemed pretty straightforward about disclosing it.