Late on a steamy early-summer night in lower Manhattan, the coolest spot to be found is Kenmare, the city's reigning It Restaurant. A clutch of blondes in head-to-toe white chat over watermelon martinis at the bar as they wait for a table, their metallic bangles mirroring the gold Art Deco room divider. In the main room, parties of four and six chat animatedly as they tuck into Mediterranean comfort food. In contrast to the rustic-moderne look of so many of its peers, Kenmare offers a tasteful mix of marble tabletops, minimalist wall sconces, and vaulted stucco ceilings—a "bohemian chic, Amalfi Coast-in-the-seventies vibe," as co-owner Nur Khan puts it—with tanned, mediagenic diners to match. The decibel level is almost as high as the beauty quotient.

Since opening in April, Kenmare has often been called, rather accusatorily, a club. That's thanks in part to Khan's past endeavors, including the Rose Bar in Ian Schrager's remodeled Gramercy Park Hotel and Hiro Ballroom in the Maritime Hotel. But that perception has been shaped even more by Khan's partner Paul Sevigny's old place in the West Village, the Beatrice Inn—a low-ceilinged former speakeasy that was a favorite haunt of Heath Ledger, the Olsen twins, Kirsten Dunst, and Mark Ronson until neighbors' complaints forced it to close last year. This could help explain why Khan and Sevigny opted to open a restaurant this time. And make no mistake: Though it does have a cavernous downstairs lounge, Kenmare is a restaurant—it's just that it caters to the kinds of people who used to be on the list at the Beatrice.

So, it seems, do all the hot new nightlife spots: Abe & Arthur's, a multilevel eatery and lounge that opened last year in the meatpacking-district space formerly occupied by the club Lotus; the Lion and the Waverly Inn, clubhouse-like joints in the West Village; and La Esquina, an underground brasserie in Nolita—when it opened in 2005 with a secret entrance, late-night ambience, and guests like Jay-Z and Beyoncé, it seemed like a novelty, not the harbinger of a paradigm shift. In Los Angeles, the new places to see and be seen are dinner stops like the Philippe Starck-designed Bazaar at SLS in Beverly Hills and the recently reopened Hatfield's in Hollywood. In West Hollywood, a new branch of the members-only clubhouse-restaurant Soho House, already an institution in London and New York, opened in March with a pre-Oscar fête that drew Madonna, J.Lo, and Natalie Portman; yet another outpost will open in Miami Beach this fall ("LeBron, party of three?"). "People you would ordinarily see at a nightclub, now you're seeing them at a restaurant," says Waris Ahluwalia, a Kenmare regular who daylights as a jewelry designer and an occasional actor in Wes Anderson films.

You might call this a recession-abetted correction. Gone are the days when the flash of an AmEx black card could get you a table behind a velvet rope; the late-night restaurant scene fosters a more communal mix that recalls the eclectic energy of the pre-bottle-service club scene. Though plenty of places still set aside tables for VIPs, many of the choice new spots don't even take reservations—they pride themselves on their support of equality, and they offer an experience that's far more filling than a $1,000 bottle of Cristal. "What do clubs sell?" asks Steve Lewis, a veteran New York nightlife columnist and club designer. "Air. They sell air, and they sell liquor." Which is why once the cash cow of bottle service dried up, many nightclubs (those that remained, anyway) started offering proper menus. Problem is, they're not very adept at making food. "Who would admit to going out to have a great meal in a nightclub?" asks Lynn Wagenknecht, who once ran the legendary West Village club Nell's and now operates several trendy Manhattan eateries. "If you want great food, you go to a restaurant." But where hot restaurants used to be the pre-party, now increasingly they are the party, beating clubs at their own game with DJ booths and dance floors and leather banquettes along with the fine dining. "It's trying to scratch multiple itches," says La Esquina co-owner James Gersten, "so you can have a meal with really great service and have fun, all in one place." As clubs struggle to survive (or simply shutter, like Cain Luxe in West Chelsea and Area in West Hollywood), restaurants are rendering them less and less relevant.

And so the openings that have gotten the nightlife circles buzzing have not been clubs, but clubby restaurants backed by celebrity chefs: Besides Kenmare, the Lion, and Abe & Arthur's, there's Má Pêche, the new midtown outpost from Momofuku mastermind David Chang; and the Breslin, Spotted Pig owner Ken Friedman's meat-tastic gastropub in the Ace Hotel, which includes a 14-person chef's table inspired by the legendary Algonquin Round Table, for those who really want to put the dinner in dinner party.

Some of this restaurantmania doubtless reflects the cultural obsession with all things gastronomical, and some is tied to the fact that people are working harder and working more. "There's an earlier bedtime," says Serge Becker, the veteran New York entrepreneur who designed La Esquina and the avant-garde burlesque club the Box. Does that mean that late night has been scrubbed of sin? Not entirely. All the vices once found in clubland are still around if you know where to look. The sin has simply gotten more discreet. "Maybe Kenmare is the best example," says Ahluwalia. "Upstairs is the restaurant; downstairs is the den of iniquity." Debauchery has literally gone underground.

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Entrée New: Like iconic eighties nightlife restaurants Odeon and Indochine, today's scene-ish eateries, like Kenmare, let the chic satisfy their hunger—and other appetites—in a communal setting that's blessedly free of velvet ropes and bottle service.

"I feel like we created the whole restaurant-lounge thing," Richie Akiva says. By "we" he means himself and his partner, Scott Sartiano, who'd already become successful nightlife impresarios with the now-defunct West Village clubs Life and Spa when they opened Butter in NoHo in 2002. Besides nouveau-American cuisine, moody lighting, and a magnificent variety of wood paneling, the restaurant has a DJ booth, a downstairs lounge called the Birch Room, and a Monday-night party. "It was a restaurant that we turned into nightlife," Akiva says.