As you saw Monday, Sir Richard Branson threw down the gauntlet, telling Arianna Huffington in the latest Digg Dialogg that he'd like to fist-fight Stephen Colbert. Well, tonight, Stephen picked the gauntlet up or threw down another gauntlet or whatever it is that people do to gauntlets when they answer fightin' words with more fightin' words. The Colbert Report airs Monday through Thursday at 11:30pm / 10:30c.