From Cliff Thies:

Intrade, one of the foremost gambling parlors in the world, now tabs Texas Governor Rick Perry as the favorite to win the Republican nomination, 33 to 32 percent, over former Massachusetts Governor Mitt Romney. Minnesota Congresswoman Michele Bachmann is a distant third, at 10 percent. Others are tabbed in the single digits.

From the Washington Times"Among bettors, Perry now bests Romney for 2012 nod":

Mr. Perry’s nomination odds reached a high of 33 percent Thursday morning, eclipsing Mr. Romney for the first time. Mr. Romney, trading at 32 percent, had been Intrade’s 2012 favorite since betting on the GOP nomination began in 2008 and had even consolidated his front-runner status in recent months as his opponents stumbled and other would-be challengers opted not to run.