He may be replacing Conan O'Brien, but the next host of "Late Night" is a Jay guy to the core. Are you laughing yet?

Many observers have noted (and hated) the way newly announced “Late Night” host Jimmy Fallon (he’s replacing Conan O’Brien) used to break character more or less continuously during his time at “Saturday Night Live.” The most prominent example of this is probably the famous Will Ferrell/Christopher Walken “More Cowbell” skit, but it happened most frequently during Horatio Sanz’s guest spots on “Weekend Update,” which Fallon co-hosted. When Sanz sensed that he wasn’t going to get many laughs with the written material (this usually happened immediately), he’d just start addressing Fallon directly, which was usually enough to set Fallon off. Fallon would smirk and bite his lip; sometimes his whole body would shake with suppressed laughter. Tracy Morgan analyzed this tendency thusly: "That's taking all the attention off of everybody else and putting it on you, like, 'Oh, look at me, I'm the cute one.'" But while it may have irritated his co-stars, and been a cheap substitute for actual humor, to be honest, I always thought it was preferable to the histrionics a lot of "SNL" cast members resort to when the material isn’t great. Fallon may have been frustrating comedy professionals and critics, but he was usually getting some laughs, well-deserved or not. That happens to be the same trade-off that Jay Leno makes every night on "The Tonight Show." As NBC announced last week, Fallon will be taking over Conan O'Brien's timeslot next year, but in every way that matters, he is Jay Leno's successor.

Like Leno, Fallon has the heart of a stand-up comedian, not a comic actor. Watch the “Cowbell” skit: While Ferrell and Walken hilariously overcommit to their absurd characters, Fallon can’t maintain his, despite not even really having a character to play. When I went to an “SNL” taping in 2002, Fallon came out beforehand to warm up the crowd, and I have to say, he was great. Sure, he wasn’t incredibly inventive in his choice of material, with a lot of jokes about college dorms and movie theaters and such, but he was still funny. It was observational humor, literally addressed to the audience--“do you remember those little fridges? They were so small!” and so forth. (I don’t remember the actual joke. It was better than that.) Such comments are of course par for the course in the “Did you ever notice/What’s the deal with ... ” school of observational stand-up, of which Leno was a pioneering member back in the ‘70s and ‘80s, when he made his reputation. This helps explain how Fallon became such a divisive figure among the pop-culture-obsessed. Here was a regular-Joe stand-up comic--a guy who builds a relationship with the audience by doing things like talking about everyday subjects, making eye contact, and smiling--shoehorned into a job that asked him to keep a straight face during skits about horny robot sharks.  

So, unlike, say, his former colleague Will Ferrell, it’s no surprise that he fizzled as an actor. When Fallon left “SNL” in 2004 he immediately headlined two major-studio films, Taxi, the nadir of his brief film career,  which involves Fallon’s cop character meeting a sassy Queen Latifah, who drives a tricked-out cab, and  the higher-quality Fever Pitch, which still flopped. And a development deal with NBC failed to produce a pilot that made the air. It all parallels Leno’s pre-hosting career exactly. Like Fallon, he was a popular comic who didn’t quite fit on the big screen. In fact, in Collision Course (1989), Leno played the white cop half of a white person/non-white person cinematic odd couple. (Summary here—good God, it’s like they’re the same movie!)

Leno eventually found a job more suited to his abilities, and when Johnny Carson’s retirement led to his hiring at “The Tonight Show” and left NBC looking for someone to replace David Letterman at 12:35, they turned to "Saturday Night Live" executive producer Lorne Michaels, who hand-picked an unknown writer for "The Simpsons," Conan O'Brien. Conan's improbable rise (probably best told by O’Brien himself here) from punchline to future “Tonight Show” host represents a huge win on a longshot bet by Michaels, and the frequently-maligned impresario deserves credit for getting it right.

Lorne Michaels, however, apparently has failed to take this success to heart. When Conan’s impending move up gave NBC the chance to start the star-making process from scratch, Michaels chose a host who’s essentially the opposite of 1992 Conan. Where O’Brien was working for the early-period “Simpsons,” a legendary factory of innovative absurdity and satire, Jimmy Fallon worked for late-period “Saturday Night Live,” the emblem of modern comedic middle-of-the-roadism: half-assed send-ups of politicians, flavor-of-the-week pop culture parodies, grating attempts to develop characters that can be turned into Lorne-produced cash-in movies featuring jokes about fat women and the white man’s inability to comfortably use hip-hop-derived slang (that last tendency has fortunately abated recently). Fallon--from his ceaseless pop culture impressions to his Taxi performance as the straight-laced white guy alongside a plus-sized, female former rapper--is the very manifestation of those tendencies.

The night it was announced, Fallon appeared on Late Night in his first interview as Conan’s official successor. Suffice it to say that he didn’t fit in well. Late Night with Conan O'Brien is the type of show where a character sings a song about his bulletproof legs before being shot in the chest. The Tonight Show with Jay Leno, on the other hand, occupies a strange place both obsessively timely and timeless, in which the most transiently amusing American Idol contestants live forever with luminaries like Bill Clinton, Michael Jackson, and Paris Hilton. Fallon made it clear which side of the line he feels most at home on, performing a long impression of Ty Pennington, the host of Extreme Makeover: Home Edition.

There's a lot of speculation that Leno, after getting the boot from NBC, will take his stylings to another network. He’s still killing in the ratings, which this smart analysis attributes to a kind of good humor impervious to crummy material. It’s the same kind of spirit Fallon exemplifies. Whether or not Leno himself sticks around, late-night viewers who so choose should be able to continue living in his kind of comedic universe for a long time.

Ben Mathis-Lilley is an editor at New York magazine.

By Ben Mathis-Lilley