LOS ANGELES, Calif. -- When NBC announced its deal to put Jay Leno at 10 p.m. weeknights I had one thought: They're not giving Conan the Tonight Show after all.

Sure, the program Conan O'Brien will host at 11:35 p.m. starting June 1 will be called the Tonight Show. But when Leno takes his signature monologue and comedy bits such as Jaywalking and Jay's Headlines to 10 p.m., whatever O'Brien does may not feel much like the Tonight Show after all.

But O'Brien, facing a roomful of TV critics Thursday night, insisted he will inherit the Tonight Show, no matter what Leno does at 10 p.m., putting the bravest face on the strangest late-night transition network TV has ever seen.

"When people ask 'Isn't this diminishing the Tonight Show?' I say, I don't need any help diminishing the Tonight Show," said O'Brien, drawing laughs. "I just think the show has to be funny."

NBC's appearance was among the most anticipated here at the TV Critics press tour, for  all the wrong reasons. Cut down to a half day, the network saw rival CBS step up and usher critics to the sets of hit shows The Mentalist and Big Bang Theory Thursday morning; critics didn't learn O'Brien would be here until just a day or two ago, leading writers to wonder whether NBC cared at all.

Eventually, NBC made some announcements: O'Brien's last show will be Feb . 20. Ex-SNL performer Jimmy Fallon takes over O'Brien's 12:35 a.m. timeslot on March 2. ER will air three more episodes, buying time for the start of ER creator John Wells' new show, Southland at 10 p.m. April 9. And another SNL alum, Amy Poehler, debuts a new as-yet-untitled show developed by Greg Daniels, creator of the American version of The Office at 8:30 p.m. April 9.

O'Brien, for his part, couldn't offer many specifics. He hopes the show, which will move to Los Angeles, will take most of its current staff, including the band. And he hopes to present a final 12:30 a.m. show that rewards fans without looking like a eulogy.

And O'Brien has just one bit of advice for Fallon: "Nobody who hasn’t done one of these shows every single day has any idea how to do it. I learned how to do one of these shows by doing. It wasn’t pretty to watch sometimes . . . But . . . my advice to Jimmy has been to get people around you who will be honest. I’m hard on myself, but I have people who tell me that was awkward, you shouldn’t have taken down your pants. The volume is so great, the pressure is so great, if you get in a bubble, you’re going to get lost.”

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