It's still perhaps a bit too early to issue a final verdict on Late Night with Jimmy Fallon, although with more than 70 episodes in the can, it can be said that The Roots remain a great hip-hop band with a great sense of humor, that Jimmy Fallon also has surrounded himself with funny comedians to write for him, and that their taped bits are generally far funnier than the sketches and "game shows" they have Fallon do with and in front of the live audience, many of which fall flat. As for Fallon himself? Well, after seeing him live in Chicago last weekend at the Just For Laughs Chicago comedy festival, I have developed a new theory on what makes Jimmy Fallon work (and what's holding him back) as a performer and as a late-night TV host. (On a brief tangent, you probably didn't know — I didn't — that Jimmy Fallon ripped his pants during his show Saturday in Chicago, as he explained in this clip during Monday night's show)

Jimmy Fallon seems most at ease when he's pretending to be someone else.

That's it. It's that simple. Fallon is uncomfortable interviewing people he doesn't know, but it's not so much because he needs to learn that skill (though he really does), as much as it's because he has not yet figured out how to be at ease just being himself on camera. Here's what he told the crowd Saturday in Chicago: "I don't watch myself (at night on TV)…I'm not that much of an egomaniac," he said. "But I do TiVo myself…and watch it all on Sundays…(to see) how much I sweat during an interview." Any discomfort he has on-air behind the desk (and we all end up sharing as viewers) goes away, it seems, whenever he can slip into a character. Any character. And it turns out he has a lot of impersonations in his arsenal — which, when combined with his musical talent, reminds you how he first got that SNL gig, and eventually his own NBC late-night showcase.

On Monday night, Fallon interviewed Nick Cannon with both of them doing Bill Cosby:

At Just For Laughs, he unleashed several more voices, including John Travolta, the Barry Gibb Talk Show (he really does love that sketch, incorporating it into an audience bit), Ty Pennington, Jerry Seinfeld, Chris Rock, Richard Lewis, Robin Williams, Norm MacDonald, Yakoff Smirnoff, Mitch Hedberg, Gilbert Gottfried, Andrew Dice Clay, Jeff Foxworthy, Larry the Cable Guy, Steven Wright and Adam Sandler — as well as musical parodies of Justin Timberlake, Katy Perry, Snoop Dogg, Green Day, Maroon 5, Amy Winehouse and a full medley of 1980s pop hits. Here is an edited version of most of that from Fallon's show the previous weekend in Bonnaroo (wearing the same plaid shirt and not-yet-ripped khakis he sported in Chicago — his lucky outfit?), after the jump…

By the way, in Chicago, he also proved he's tied to his Microsoft advertising tie-in so deeply that during a joke about food, he said this: "Turducken's real. Bing it!" Yes. He said that. An audience member also asked him to do an impersonation of Lisa Lampanelli, to which Fallon replied: "Lisa Lampanelli? I don't do her. (Pause) Write your own joke."

About the only thing we didn't see in Chicago was Jimmy Fallon's spot-on impersonation of Dave Matthews, which he showed off on TV earlier this month — alongside Matthews himself:


The guy is clearly talented, and when he's onstage, he knows how to work a crowd and have them in his corner. Now if he can just bring that same confidence and charm when he's behind the TV desk. Unless, of course, he could 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. Oh, wait. That's Leno's new 10 p.m. show. Or is it?