The Inheritance of Loss by Kiran Desai has won the 2006 National Book Critics Circle Award. (And in answer to my own question, yes, it won the 2006 Man Booker prize as well.
2 out of the past 3 years, the NBCC award winner has gone on to win the Pulitzer (and I'm convinced that last year the judges just got confused, awarding the prize to March instead of The March), so, normally this would have made Desai the immediate odds-on favorite, but the Pulitzer is specifically limited to "distinguished fiction by an American author, preferably dealing with American life," so I'm not sure Desai is eligible. (I don't know where she lives or what citizenship she holds, so she may, in fact, be eligible, but it would be extraordinarily rare to see a book win both a Booker prize and a Pulitzer. The two are usually mutually exclusive.)
Of course, no one has expressed any interest in laying bets on the Pulitzer, so it may not matter anyway.