I’m rooting for Jimmy Fallon. I want him to succeed as host of “The Tonight Show,” the first since Johnny Carson to be billed in the title as “starring” on the show and not just “with” a host by name (as in “The Tonight Show Starring Jimmy Fallon” vs. what was previously billed as “The Tonight Show WITH Jay Leno”).

I was never rooting for Conan O’Brien. He was talented, bright and funny enough. But in that “X” factor, where you searched for a simpatico human being underneath the Harvard Lampoon clowning and good breeding and abundant wit, I couldn’t find anything there – at least nothing I wanted in my living room nightly.

Except for Jay Leno, I like almost everyone else in late night more than Conan O’Brien – self-tortured legend Letterman, self-admitted addict-in-recovery Craig Ferguson, overachieving underachiever Jimmy Kimmel, self-righteous minority advocate Arsenio Hall and, yes, Jimmy Fallon, the sweet young guy who adds real musical savvy to everything else and has clearly made an act out of seeming to be in over his head even though he’s nothing of a sort.

But Conan O’Brien, to his credit, seems to be the only late night host this week who truly understands what’s happening.

The ascent of Jimmy Fallon into “The Tonight Show” throne was, in fact, a perfect opportunity for an ambitious guy like O’Brien, who once actually convinced another Harvard guy, ex-NBC head Jeff Zucker (current majordomo of CNN) to promise him “The Tonight Show” in five years. O’Brien understood that despite all the hype, Fallon’s “Tonight Show” this week is, in some ways, as vulnerable as it’s ever likely to be.

Not only is Fallon an unproven 11:30 p.m. talent, the NBC game plan for introducing him has proven faulty. They desperately wanted the Olympics to be the lead-in. Unfortunately, the Olympics have proven to be consistent in ratings with other past Winter Olympics, but apart from Bode Miller’s tears, not nearly the big chat and water-cooler generator they have been in past years.

But, because of them, Fallon made his all-important debut at midnight Monday, which virtually guaranteed many of us would DVR it and watch it later, thereby wiping out the efficacy of Fallon’s opening night advertising.

Fallon’s first guest, Will Smith, is indeed one of the most charming and irrepressible men in current show business. But Smith’s movie choices of late – as in “After Earth” – have been shaky at best. They’ve tanked, which is not a good thing. Fallon’s scheduled opening musical guest was U2, a late night rarity, true, and indeed a very good late night musical act, but one you can easily wait to see on your DVR.

It’s O’Brien, though, if you ask me, who is the only late-night talk host this week to have a must-see show in real time during Fallon’s accession to late night’s coveted throne.

This evening at 11 p.m., O’Brien will have 87-year-old Mel Brooks spend most of the show talking about Sid Caesar and the extraordinary Caesar show writer’s room, in which Brooks was the maniac-in-chief. (Caesar, reportedly, would affectionately bend Brooks’ head toward him, kiss the top of it and say, “This is all MINE.” Whereupon Brooks would reach around, grasp the wallet in Caesar’s back pocket and yell, “And this is all MINE.”)

If Brooks, at his age, is still in good form, it could well be classic television.

Wednesday night, O’Brien’s guest will be Ray Romano, another talker who actually has the capacity for stealing a “real time” audience away from Fallon’s first week.

So too did David Steinberg on last night’s “Inside Comedy” interview on Showtime with Bette Midler and Richard Belzer.

Otherwise, I’ve looked at the scheduled guests on all the major late-night talk shows for this week and it seems almost as if Fallon’s fellow New York-based host – Letterman – didn’t even bother trying to mount serious ratings competition.

He countered Fallon’s opening night with Kevin Spacey, Amber Heard and Gary Clark Jr., a nice, business-as-usual Letterman show if nothing else were happening elsewhere that night.

After that, his scheduled list is full of Olympic snowboarders, lesser Oscar nominees and CBS series favorites (“NCIS’” Pauley Perrette, for instance, appears Friday, to exhibit the remarkable longevity of professional adorableness.)

Jimmy Kimmel, smartly, made an effort to compete. He countered Fallon’s opening show with Jennifer Lopez. He’s got Bill O’Reilly this evening, Matthew McConaughey and June Squibb for an Oscar-schmooze Wednesday and Jonah Hill for another on Thursday. He’s using his hegemony in Hollywood now to his major advantage.

After Will Smith on the opener, Fallon’s first week guest list is a juggernaut: Jerry Seinfeld and Kristen Wiig and Lady Gaga tonight; Bradley Cooper and Tim McGraw Wednesday; Michelle Obama, Will Ferrell and Arcade Fire on Thursday; and Justin Timberlake on Friday.

Is is any wonder, we might ask, that Letterman stuffed his show with Olympic snowboarders? His strategy, obviously, is to concede the opening week to Fallon and get back into the game later.

What’s logical though is that if Fallon is any good at all this week, his guest list may indeed give him the great leap forward into audience affection that Jay Leno could never quite achieve, even as he was always leading the pack in numbers (which should tell anyone who’d want to know just what’s wrong with numbers and numbers alone).

The argument made by self-hating baby boomers (and those older) is that the current late-night talk format is an archaic relic of an older era that isn’t remotely relevant in the digitally miniaturized attention spans of the YouTube and Facebook Twitterverse.

To the degree that it’s true, all previous civilization is, in effect doomed. That is, then, not the best way to proceed.

What I prefer to think is this: The situation is merely crying out for wholesale reinvention by a palpable, identifiable human being who will give people of all demographic persuasions someone they don’t mind in their living rooms and bedrooms before they go to sleep.

Someone, you know, like that boy Jimmy, the nice, smiling, talented, popular boy next door whose music is sometimes loud but pretty good and never goes on too long.

As I said, I’m rooting for him.