To most of the reading public (including me) this looks like a classic example of the politicization of the Nobel Prizes -- however I've consistently found very smart economics that I read online to say that Krugman is in fact a very good economist when he's dealing with economics, though a total hack when writing for the NY Times.
For those interested in reading about "the other Paul Krugman", Marginal Revolution provides a good and readable explanation of Krugman's academic work, and his achievements in trade theory. Also readable (and very short) is Arnold Kling's post on EconLog.
Dashed Off II
48 minutes ago