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The news that Jay Leno is expected to return to The Tonight Show, leaving Conan O'Brien out in the cold, prompted a bitter night of barbs on their respective shows Thursday, with a third late night host, ABC's Jimmy Kimmel, hopping into the fray. "Sarah Palin has signed on to Fox News to be a correspondent," Leno said in his opening monologue. "Well, in a statement today, Fox said that—if Palin does a good job—they'll sign her to a long-term contract. If she doesn't work out, they'll just blame Leno." In a satellite appearance on the same show, Kimmel left little doubt which side he was on with multiple attacks on Leno to his face. Asked by Leno to name the best prank he ever pulled, Kimmel said it was when "I told a guy that five years from now I'm going to give you my show. And then when the five years came, I gave it to him, and then I took it back almost instantly." Finally, Conan addressed rumors that NBC might try to block him from going on air if he were to leave his show by suggesting "If NBC doesn't want people to see me, just leave me on NBC."