The network announced Wednesday what has been rumored for the past several weeks: Leno will leave the job he's had most of the time since 1992, to be replaced by "Late Night" host Fallon. The late-night franchise is also returning to its roots, leaving California for a New York studio.
The thinking is clear: Leno is 62, his hair graying. The eager Fallon is 38, looks younger, hangs with his ultra-hip house band the Roots and slow jams the news with President Obama.
All Leno does is consistently rank No. 1 in his field, a status not many people at NBC can claim these days.
The "Today" show was tops a year ago, too, or at least running neck-and-neck with ABC's "Good Morning America." Then the toppling of co-host Ann Curry spread a black cloud. Ratings tumbled, executives lost their jobs, Matt Lauer's popularity plummeted and "GMA" is now the most popular morning show.
Could history repeat itself at the same network?
"I'm sure the people at (corporate owner) Comcast and NBC are keeping their fingers crossed that it's not another public relations black eye," said Brad Adgate, analyst for Horizon Media.
NBC's hand was forced, to its perspective, by ABC when that network put Jimmy Kimmel in the time slot shared by Leno and CBS' David Letterman earlier this year. Young people are already seeking out other entertainment choices in late-night, and NBC didn't want ABC to establish itself as the network with the young, hip host right after the local news.
"We are purposefully making this change when Jay is (hash)1, just as Jay replaced Johnny Carson when he was (hash)1," said Steve Burke, chief executive officer of NBC Universal, in a statement. "Jimmy Fallon is a unique talent and this is his time."
Burke was not made available for an interview to discuss NBC's reasoning and whether the network applied any lessons from the Curry mess to its late-night switch.
The most pressing question is whether Leno's fans warm to Fallon, or if they use this as an opportunity to try something else. Leno's fans did not accept Conan O'Brien in 2009 when he took over "Tonight" for less than a year. Fallon's humor is broader than O'Brien's, and would seem a better fit.
Leno also presumably won't be around for a direct comparison this time. When O'Brien worked at "Tonight," Leno was in the midst of his failed prime-time experiment on NBC.
There's no telling whether fans of Leno will resent the network's treatment of the comic the way morning viewers took out their distaste for what happened to Curry on "Today." NBC is dislodging him from late-night for the second time; what did he do to deserve the door?
Viewers might also question the network's regard for them. Why is NBC taking my favorite comic away?
Letterman, while he's been no big fan of his rival Leno through the years, was already pushing this narrative on his own show Wednesday, taped shortly after NBC's announcement.
"How many times can a guy get pushed out of the job?" Letterman asked. "What's the matter with NBC? What's the matter with these guys? You know, honestly, what are they thinking?"
He congratulated Leno on his 'Tonight' tenure, "if in fact you're not coming back."
"It's difficult to give up a program that wins its time period by 33 percent, and Jay has always been a great friend to the affiliates," said John Dawson, general manager for five NBC affiliates in Kansas. "For that alone it will be hard to give him up. But I believe in Jimmy's ability to retain Jay's viewers and to bring his own unique audience to that time period."
NBC is timing the change for maximum impact. It will happen around the Winter Olympics in Russia, which is expected to give the network a large prime-time audience that will be peppered with promos.
Barring a major change in NBC's sagging prime-time fortunes, Fallon will quickly be on his own when the Olympic flame is extinguished.
The Curry debacle was punctuated by her tearful last day as host in June, a deeply uncomfortable television moment. She has largely been silent since, as NBC has tried many different ways to convince "Today" viewers that they shouldn't blame Lauer for an unpopular decision.
NBC says privately that Fallon has tried judiciously to make sure Leno was on board with the move, and that Leno has a higher regard for Fallon personally than he did for O'Brien. A few years down the line, Leno may be more ready to end his "Tonight" tenure than he was before.
NBC has taken pride through the years in orderly transitions — like when Brian Williams took over for Tom Brokaw, and Meredith Vieira replaced Katie Couric. It will put the machinery to work to make this one seamless, too. Or at least appear that way.
There was a rocky start. When Leno needled NBC executives about their miserable prime time ratings this winter, it hit a nerve with NBC Entertainment President Robert Greenblatt. He sent a note telling the comic to cool it. That approach backfired when the note became public and Leno hammered his network even harder.
The first public sign of the coming transition came Monday night, when Leno and Fallon filmed a genial spoof together making fun of all the late-night rumors. It aired between their two shows.
"It's clear they are trying to stave off negative reaction," said Christine Becker, an associate professor at Notre Dame University and author of the News For TV Majors blog. "I don't know whether it's going to be successful or not."
That's because of a sense that there's still something missing, she said.
"Jay is saying really nice things, but what really is the deal?" Becker said. "Did Jay tell them that he wants to go? Will he go someplace else? ... NBC is struggling to play the PR game and make it work but there are so many gaps and holes that it makes it strange."
Associated Press television writer Lynn Elber in Los Angeles contributed to this report.