"Yes, we have our differences right now and yes, we're going to go our separate ways," O'Brien said of NBC, his employer of 17 years. "But this company has been my home for most of my adult life. I am enormously proud of the work we have done together, and I want to thank NBC for making it all possible."
O'Brien, who had announced just 10 days earlier that he would rather leave The Tonight Show than accept a move to after midnight to accommodate Jay Leno's return to the 11:35 slot, said walking away "is the hardest thing I have ever had to do."
He also thanked fans who pledged their support throughout his negotiations with NBC, which ended with a $45 million exit deal for himself and the people he described Friday as "the best staff and crew in the history of the medium."
Walking out to his final standing ovation as host, O'Brien notified the audience: "Ladies and gentlemen, we have exactly one hour to steal every single item in this studio."
"We've had a lot of fun being here these last seven months," he added. "But like everything in life, the fun has to come to an end a decade too early."
He also joked about what would become of his studio, saying it might become "a nice, quiet, peaceful place where the cast of Chuck can be alone with their thoughts" or be left cold and empty to serve as "The World's Largest Metaphor for NBC Programming."
To the tune of Cheap Trick's "Surrender," which also accompanied the cross-country intro of his first Tonight Show episode, he introduced a montage packed with a remarkable number of memorable moments for just seven months: His domino-style toppling of actual Domino's Pizza employees, a fake miracle for the benefit of tram-bound tourists, his sprint across Wrigley Field, one of many recent appearances by his hunky vampire assistant, Cody Devereux.
It ended with the encouraging words, "To Be Continued."
Other highlights of the night included a corporate exit interview with "NBC employee" Steve Carell, who collected O'Brien's ID badge, and an interview with Tom Hanks, who recalled meeting the man he has dubbed "Coco" during his days as a Saturday Night Live writer.
Hanks and musical guest Neil Young, who performed his 1976 song "Long May You Run," also appeared in Friday night's Hope for Haiti telethon. O'Brien repeatedly ran the web address hopeforhaitinow.org across the screen during the show.
O'Brien leaves NBC barely 11 months after signing off as host of Late Night With Conan O'Brien. That goodbye was a nostalgic but hopeful affair that included the fan-pleasing announcement that his former sidekick, Andy Richter, would rejoin him for The Tonight Show.
O'Brien assured fans then that his menagerie of beloved characters, including Triumph the Insult Comic Dog and Masturbating Bear, would follow him to The Tonight Show.
But he can make no such promises now. Under his exit deal, NBC retains the rights to his characters and routines.
Fox, which employed O'Brien as a writer for The Simpsons from 1991 to 1993, has expressed interest in hiring him as a late-night host. But O'Brien gave no indication Friday where he might end up, except to say this:
"I've had more good fortune than anyone I know and if our next gig is doing a show in a 7-11 parking lot, we'll find a way to make it fun."
He also asked fans not to be cynical.
"I hate cynicism — for the record it's my least favorite quality and it doesn't lead anywhere. Nobody in life gets exactly what they thought they were going to get. But if you work really hard and you're kind, amazing things will happen. ... As proof, let's make an amazing thing happen right now."
And with that, he introduced his final Tonight Show guest (who had also been his first): a cowbell-wielding Will Ferrell, who led Beck, Ben Harper, ZZ Top's Billy Gibbons, O'Brien's band, and O'Brien himself on guitar for a rendition of "Free Bird" that was, indeed, amazing.