A nostalgic Jimmy Fallon signs off on 'Late Night'

Jimmy Fallon, who will begin hosting the 'Tonight Show' in 10 days, bid farewell to his 12:37 p.m. slot on 'Late Night.' Fallon's house band the Roots and his announcer will also move to 'Tonight.'

It's not so much "goodbye" as "taking a break."

With Jimmy Fallon's departure from "Late Night" on Friday after five years in the host chair, he'll be off the NBC airwaves a scant 10 days before bouncing back as host of "The Tonight Show," which was vacated Thursday by Jay Leno after 22 years.

"I'm really going to miss being on TV at 12:37," Fallon joked in his farewell monologue, where his "fierce rivals" have been CBS host Craig Ferguson "and a Veggie-Chopper infomercial."

But if he was overjoyed at graduating to a berth one hour earlier — and all through the finale he radiated joy — at the same time he could hardly keep his tear ducts in check.

"I'm not gonna cry," he vowed, "but I'm gonna get really close."

"You got to pull it together, man," teased his very last guest, fellow "Saturday Night Live" alum Andy Samberg.

"'I'm just a big ol' moosh. 'Irish Moosh' was my nickname in high school," replied Fallon.

The 39-year-old Fallon has promised that nothing much will change with his talk-comedy-music formula, except the new time slot and "Tonight Show" prestige.

But if it's not so big a change for Fallon (or his house band, the Roots, or his announcer, Steve Higgins, who all are coming along), it's a big change for "Tonight," which is returning to New York's Rockefeller Plaza after more than 40 years in Los Angeles, and returning to NBC's Studio 6B, once inhabited by "The Tonight Show Starring Johnny Carson."

To complete this game of musical chairs, Seth Meyers (another "SNL" grad) becomes "Late Night" host starting Feb. 24.

"We're gonna be a great team back-to-back," Fallon said.

During his monologue, Fallon got nostalgic, with a dash of comedy. He said since premiering in March 2009, he had spun out 10,000 jokes, all of which he proceeded to sum up as: "Joe Biden needed Obamacare after Anthony Weiner texted Justin Bieber a picture of Chris Christie dating a Kardashian on the Jersey shore with Rob Ford."

More sincerely, Fallon voiced thanks to David Letterman for launching "Late Night," and to Conan O'Brien, its second host, as well as to his viewers, whose support "means the world to me. It makes me so happy."

The hour ended with a big musical number: Fallon on drums and singing the Band classic "The Weight," accompanied by a large ensemble of Muppets, complete with Kermit and Miss Piggy.

Then he made his exit from his longtime "Late Night" home, Studio 6A, and strode a few steps down a hallway to his soon-to-be new home. He opened the door to Studio 6B, identified as "The Tonight Show Starring Jimmy Fallon," to find a cheering, welcoming throng. Fade out.

That's awaiting him for real in just 10 days.