In January 2010, NBC announced that Jay Leno, host of The Tonight Show with Jay Leno (1992), from whom Conan O'Brien took over the role as host, would have his not-so-well-received The Jay Leno Show (2009) move towards the 11:35 PM time-slot and that The Tonight Show with Conan O'Brien (2009) would be pushed back to the 12:05 AM time-slot. "The Tonight Show" has never aired that late during its almost 60 years on air. Furthermore, this push-back would have meant that Late Night with Jimmy Fallon (2009), follow-up to O'Brien's own Late Night with Conan O'Brien (1993), would also have been pushed back to a later time-slot, too. When The Jay Leno Show (2009) was officially canceled and it became clear that Leno would get his own new show at 11:35 PM, O'Brien released a statement in which he made clear that he didn't like how NBC handled the situation. He also stated that he wouldn't continue hosting The Tonight Show with Conan O'Brien (2009) if it was pushed back to a later time-slot. Eventually that month, it was officially announced that Leno would get "The Tonight Show" back on March 1st and that O'Brien will receive a severance payment of about $33 million from NBC.
On the episode of November 18, 2009, Conan O'Brien said Heidi Montag and Spencer Pratt are on the show and the audience booed. On the next day's episode, Conan said, "In 17 years in this business, I've never heard an audience respond like this."
The final episode of The Tonight Show with Conan O'Brien garnered a 4.8 rating in the demographic of adults 18-49, which was over 40% higher than the 3.4 rating for the 2009 finale of The Tonight Show with Jay Leno.
During the time of the "Late Night Wars", in January 2010, in which NBC was re-scheduling its Late Night-program, there evolved the "I'm with Coco" movement, which favored Conan O'Brien over Jay Leno as host (of "The Tonight Show" or anything else) and thought that NBC's behavior towards O'Brien was rude and unfair.
When Conan O'Brien announced (on January 13, 2010) that he wouldn't continue to host the show if it would be pushed back to another time slot to air, he rather abruptly ended his stint as host of "The Tonight Show". The last episode of The Tonight Show with Conan O'Brien (2009) aired on January 22nd, 2010. O'Brien remained under contract with NBC until September 1, 2010.