Jimmy Fallon Thanks Jay Leno on ‘Late Night’ (Video)

Jimmy Fallon thanked Jay Leno on Wednesday's Late Night on the heels of NBC's confirmation that he'll take over The Tonight Show next year.

"I want to thank everyone here at Late Night, the staff, the crew and, of course, The Roots," he said during the taping. "I have to say thanks to Jay Leno for being so gracious. It means so much to me to have his support. I just want to thank the fans for staying up to 12:35 a.m. and watching us."

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His remarks came just hours NBC made its official announcement that Leno will be stepping down as Tonight Show host in spring 2014 and will be replaced by Fallon, who also addressed the news in his monologue.

"Hello! Welcome! This is Late Night With Jimmy Fallon -- for now," he said. "You guys probably heard the news -- I’m going to be taking over The Tonight Show next February! But don't worry. Until February, our focus is right here on whatever this show is called."

Meanwhile, sources tell THR that Fallon's staff gathered after the taping of Late Night on Wednesday to toast the news.

Earlier this week, Late Night aired a musical segment in which Leno and Fallon dueted on a version of "Tonight," from West Side Story, in which they addressed NBC's late-night woes.

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NBC confirmed the news a month after The Hollywood Reporter revealed that the network was preparing an exit plan for Leno. THR reported Tuesday that Fallon had signed the Tonight deal and that Saturday Night Live stalwart Seth Meyers is being eyed as his Late Night replacement.

When Fallon takes over, Tonight Show will return to 30 Rockefeller Plaza in New York, where it will be executive produced by Fallon's former Saturday Night Live boss Lorne Michaels.

David Letterman also made jokes about the late-night shake-up in his monologue and even did a Leno-themed top 10 list on Wednesday night's Late Show.

"I mean, how many times can a guy be pushed out of the job, I mean," Letterman said to his audience. "And what’s the matter with NBC? What’s the matter with these guys? You know, honestly, what are they thinking?… And, as with everything in life, all I really care about is how will this affect me? That’s all I really care about. And, Paul, is there any way NBC can push me out of this job? Can they do that?"

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Leno has been host of Tonight Show for 22 years, save for seven months in 2009-10 when Conan O'Brien took over and Leno launched a short-lived primetime show on NBC.

Kimberly Nordyke