When Jay Leno took over The Tonight Show from Johnny Carson in 1992, there was no visible late-night TV war to be waged. At 11:30 p.m. Eastern/Pacific, there was The Tonight Show, or there was Arsenio Hall. Leno’s ascension over David Letterman, however, revealed a civil war within NBC that wasn’t at all civil for the next two years, as Letterman bolted Late Night for the greener pastures of CBS, the Ed Sullivan Theatre and the Late Show.

NBC hoped by remembering its history, it would not repeat it in 2009, giving Leno a five-year warning before giving his Tonight Show to Conan O’Brien. But NBC’s repeated votes of no-confidence in both Leno and O’Brien sparked an even uglier civil war within the Peacock Network’s feathers that gave rise to Team Coco, provoked a series of Leno jokes from Letterman and Jimmy Kimmel — and though Leno got his Tonight Show back and O’Brien earned a new home and earlier time slot with Conan on TBS, there weren’t really any winners of this war.

Unless you’re Jimmy Fallon. Lorne Michaels picked Fallon to succeed O’Brien at Late Night in 2009, and five years later, he’ll start hosting The Tonight Show starring Jimmy Fallon on Monday.

Fallon and his crew aren’t packing up stakes and moving across the country to Burbank, Universal City or Hollywood; they’re moving across the hall to the studio they were just in for most of their first five years — the same studio Johnny Carson’s Tonight Show broadcast from in 30 Rockefeller Plaza before Carson went west more than four decades ago. And Fallon and Leno appeared together in sincere music videos and back-patting interviews to assure us all that 2014 is not 2009 nor is it 1992 all over again.

No. It’s not The Late-Night TV Wars III. Actually, it’s more of a Late-Night Melee than a war. The landscape facing Fallon is so much more fractured and segmented as at least a dozen other hosts are competing for our attention after the late local news. And that’s even if we’re watching the shows late at night.

Fallon has so much going for him already before his first Tonight Show airs Monday night. For one thing, he still has Lorne Michaels in his corner. Lorne, who also had handpicked Conan O’Brien, didn’t executive produce O’Brien’s Tonight Show so didn’t have as much at stake in his success — now Lorne is EP on everything that happens from 11:30 p.m. to 1 a.m. on NBC from Mondays-Saturdays, with Fallon, the new Late Night with Seth Meyers and his first baby, Saturday Night Live.

Leno’s advice for Fallon, as the latter has been quick to recite in interviews, was to double his monologue. But might be the least effective advice Leno could have given him. Viewers don’t turn to Fallon to hear him be funny. They seek him out because he is fun, with a capital F-U-N. Leno may have held onto “#1 ratings” however the network and Leno’s team wanted to slice it, but among younger viewers — and that’s what this switch is all about — they’re not getting their daily jokes from Fallon, if they’re getting them from TV at all. They already read so many daily quips on Twitter and Facebook, and watch takes on topical news on YouTube. If they want serious take-downs, they turn to Comedy Central for The Daily Show with Jon Stewart and The Colbert Report with Stephen Colbert. They can get downright silly sticking with Comedy Central afterward for @midnight for everything crazy that was passed around the Internet that day. Fallon? His best way of delivering you the news is to Slow Jam it with The Roots, with Brian Williams or even President Barack Obama backing him up. Every Friday, Fallon expresses his appreciation for the week’s weirdness with his Thank You Notes. He doesn’t need a monologue.

Moreover, Jimmy Fallon isn’t really even a talk-show host. Not in the classic sense. And that’s a very good thing. As I raised in my initial review of Fallon on Late Night back in 2009, Fallon is at his best when he’s away from the desk letting loose and getting into character. His Grammy-winning album, “Blow Your Pants Off,” is testament to his talent as a musical impersonator and collaborator — he attracted duet partners in Sir Paul McCartney, Bruce Springsteen, Eddie Vedder, Justin Timberlake, Big & Rich, Dave Matthews and even Colbert. Before then, I had expressed hope that he’d ditch the desk and “convince NBC to scrap that part of the show altogether and make it more of a comedy-variety hour that just so happens to have celebrity guests.”

Recurring parodies of TV from Joking Bad to Late, Jersey Floor, Downton Sixbey, The Real Housewives of Late Night, 6-Bee, and then live parody sketches allow Fallon to bring his SNL experience to weeknight late-night. Celebrity Charades and Beer Pong were games you could have seen on Leno’s ill-fated 10 p.m. experiment, and are enjoyable enough on Hollywood Game Night that NBC would rather air that than place its faith in 1980s/1990s sitcom stars Sean Hayes and Michael J. Fox for another Thursday.

When Fallon raps with Timberlake or gets The Roots to jam with another musical hitmaker, it doesn’t matter if you watched it at 12:37 a.m. or 1:37 a.m., because your friends will let you know about it less than 12 hours later via email and social media.

That’s the world we live in in 2014, wherein late-night boobtube is more about what you’re watching on the morning YouTube.

And in this world, Fallon is just one of many. But already a very successful one.

The late-night TV landscape — which starts at 11 p.m. Eastern/Pacific, 10 p.m. Central/Mountain — now includes this crowded field (times listed below are Eastern/Pacific)

11 p.m.

The Daily Show with Jon Stewart (Comedy Central), Conan (TBS), The Arsenio Hall Show (syndicated), Chelsea Lately (E!), Watch What Happens Live (Bravo), Olbermann (ESPN2), Charlie Rose (PBS), American Dad reruns (Adult Swim). Also in syndication: The Big Bang Theory, How I Met Your Mother.

Jon Stewart’s half-hour skewering of TV news and serious discussions with authors and politicians is the top choice for a plurality, if not a majority, of younger viewers when it airs in late-night. Team Coco has settled into a groove as comfortable as the one it originally had 90 minutes later on another network and another side of the country. Conan’s Conan is, perhaps ironically, closer in spirit to Johnny Carson’s old Tonight shows — from the live sketches to the sidekick who remains by his side and the lively panel discussions — than anything else on the dial. Even if it is on TBS. Andy Cohen presides over a live, free-wheeling, drinking-game half-hour on Bravo that’s tailor-made to the folks already tuned in to whichever “Real Housewives” or other “family” is misbehaving an hour earlier. If you want to make fun of those people and the tabloids who cover them, Chelsea Handler’s got that on lockdown with her rotating panel of three stand-up comedians and one Chuy on E!’s Chelsea Lately. And if you want a real throwback, Arsenio is partying like it’s 1991 and 2014 simultaneously with Arsenio. Let’s do the time warp, yeah? Meanwhile, you can find Keith Olbermann on ESPN2 and Charlie Rose on PBS waxing and waning in late-night opinions and interviews, respectively. Or you can stick with reruns of sitcoms.

11:30 p.m.

The Tonight Show starring Jimmy Fallon (NBC), Late Show with David Letterman (CBS), Jimmy Kimmel Live (ABC), The Colbert Report (Comedy Central), Family Guy reruns (Adult Swim). Also: 30 Rock, How I Met Your Mother.

Fallon and Stephen Colbert were TV “BFFs” and friendly rivals, so it’ll be interesting to see how they play that up now that they’re on in the same time slot. David Letterman now becomes the elder statesman of late-night TV that he already was, an influence to so many of the other white men on this list. For every viewer who will tell you that Letterman is cranky and doesn’t want to be there, you’ll find two other viewers who think Letterman has never been better, ready to mix it up with compliments, insults, good-natured and even not-so-good-natured ribbing, depending upon the lead celebrity or celebutard seated beside his desk. Jimmy Kimmel, meanwhile, has proven himself not only the true disciple of Letterman — but also decidedly taken notes on Leno and the Internet. Kimmel dispatches his camera crew outside along Hollywood Boulevard to dupe apathetic pedestrians into revealing how little they’re paying attention — a keen update on Jaywalking if we’ve ever seen one. He’s also duped local TV newscasts nationwide into replaying his “viral videos” before revealing them to be backed by Kimmel. Colbert’s “Stephen Colbert” remains, above all, the best antidote to any time spent listening to the hot blustery b.s. air spewn forth from talk radio and “talk” cable TV. Or there’s still sitcom reruns, for those who still seek comfort in what’s already made them laugh before.

Midnight

@midnight (Comedy Central), The Pete Holmes Show (TBS), Robot Chicken (Adult Swim). Also: 30 Rock, The King of Queens, Seinfeld.

At midnight, viewers uninterested in the celebrity guests on Letterman, Kimmel or Fallon have a clear choice on their cable dials. @midnight is a fast-paced “game show” in which host Chris Hardwick tries to shout “POINTS!” as fast as his three comedian guests can toss out quips based on real-life/suggested Twitter #hashtags, Yelp reviews, OKCupid profile pictures or Reddit threads. It’s a half-hour that goes by quickly, and if you’re on Twitter, it may seem maddening as everyone and your friends (myself included) gets caught up in the hysteria of hope that is seeing your Twitter avatar and Tweet on the TV the following night. Over on TBS, Team Coco has renewed The Pete Holmes Show, which is a fascinating hybrid of a show. Holmes doesn’t tape his monologues same-day, and tapes his field pieces even earlier, so there’s a timelessness to the proceedings. You can watch Holmes at midnight that night, or DVR it and watch it anytime and get the desired effect. What is the desired effect? Catching the infectious humor of host Holmes, whose podcast is “You Made It Weird” and TV philosophy is Nothing Is Weird Because We’re All Weird. As he told The Comic’s Comic before his show comes back from reruns next week: “Season two will be all about taking what we started and running with it. so more non-topical, personal monologues, more sketch like Badman and X-Men, and more interviews, especially off-set remote interviews like the one we did with Allison Williams, just to help us stand out in feel from the other desk-centered shows.” Or you could still switch over to reruns.

12:30/12:37 a.m.

Late Late Show with Craig Ferguson (CBS), Late Night with Seth Meyers (NBC).

Craig Ferguson is a Scottish-American (dual citizenry FTW!) who likes to rip up his cards, throw away the script and talk to a robot skeleton when he’s not talking up his guests. He’ll joke that nobody’s even bothering to watch his show, and then act as though he’s directing his show directly at you at home. Ferguson puts the talk in talk shows, and always delightfully surprises you and his guests alike. With Seth Meyers, who knows what we’re going to get? Well, we can guess it’ll be a lot more like an SNL spin-off. If Jimmy Fallon’s SNL spin-off plays up the sketches, fun and games, then Meyers is definitely the Weekend Update that follows. Not just because that’s how most of you know Meyers in the first place. He’ll also have Fred Armisen leading the band and several of his past co-workers coming to visit him in character. Just like a wedding reception, perhaps Meyers will offer something old, something new, something borrowed, and maybe even something blue.

Come on back in a few months and we’ll see how this all continues to shake out.

Photo illustration above via Gluekit, WSJ.