Transitions aren't always so smooth. When Deborah Norville took over Jane Pauley's post on the "Today" show in 1989, she did so under a wave of speculation that her good looks and youth forced NBC to oust Pauley from her anchor chair too early. Viewers flooded the network with thousands of outraged phone calls and letters following the announcement that the then 39-year-old Pauley was ceding her spot to Norville after 13 years.
''If I'd been a 31-year-old man going on as news anchor, there wouldn't be nearly as much ink about this," Norville told The San Francisco Chronicle in 1989. "Are we saying that women can't share the same masthead on a publication or work in a law firm together? It's out-and-out sexism, and it denigrates the years I've spent trying to grow as a reporter."
''Jane and I are friends and, when you know the real story, it hurts to see the way it was depicted," she added.
For better or for worse and luckily for O'Brien, audiences seem to be more open to change when it comes to leading men and late-night TV. What follows is a comparison that O'Brien -- who depending on the day, likens himself to a leprechaun, a little girl and the female president of Finland -- would find laughable. Nevertheless: taking over "The Tonight Show" is kind of like becoming the new James Bond. Both gigs come with a sidekick (sure, Bond's are better looking), a killer wardrobe of suits, and of course, large legacies to live up to. Replace Sean Connery's name with Johnny Carson's and Pierce Brosnan's tale below rings true for O'Brien:
"I remember [Sean] Connery walking that walk more than 20 years ago," Brosnan said in 1995, on the eve of the release of his first Bond movie, "GoldenEye." He told The Orange County Register: "It's not something an impressionable young lad forgets, and Connery indeed casts a long shadow on this role. But you arrive on the set and you have to walk the walk. You can't think about Connery or [Timothy] Dalton. There's no getting away from it; you just have to do it. You have to trust yourself and know that you can do it. You're the man now. You're James Bond for a new generation."
ABC News Research's Melissa Lenderman contributed to this report.