That star took a considerable tumble last fall, following a brutal review of Mr. Love’s newly opened Lonesome Dove Western Bistro on West 21st Street.

Call it the Bruni Effect.

New York Times restaurant critic Frank Bruni’s eviscerating critique began outside the gamey Flatiron-district eatery, comparing the soggy and trampled steer’s hide at the doorstep to “roadkill after a rainstorm.” Inside, Mr. Bruni noted a “morose” vibe, accented by “mud-colored walls and bad lighting.” And the food? A “bruising slam dance” of flavors and ingredients.

Other factors probably contributed, but Lonesome Dove didn’t last long after Mr. Bruni’s stinging zero-star rating; the belittled venue hung on for a few short months before finally shuttering in March.

“Of course reviews impact business,” e-mailed Mr. Love, who otherwise declined to “bitch or complain about any one person’s opinion.”

Varietal, on West 25th Street, felt an almost immediate Bruni Effect. An executive chef and pastry chef both reportedly resigned within days of Mr. Bruni’s March 21 write-up, which highlighted an appetizer that tasted like “laundry detergent” and desserts that looked like someone “took a mallet” to the confections and “let the shards and crumbs scatter where they may.”

Even in an era where the Internet allows anyone with an appetite to act as critic, The Times’ top foodie still wields considerable power to boost careers and crush dreams. Not that Mr. Bruni himself would use such make-or-break terms.

“I have no way of knowing whether a review I’ve written hastens the death of any restaurant,” Mr. Bruni told The Observer, “but I can assure you it’s not my goal in writing a negative review to put a restaurant out of business. I’m just writing what I honestly think about the restaurant, with my principal consideration being readers and consumers.”

Mr. Bruni was appointed the food critic in April 2004, leaving his role as Rome bureau chief for The Times after a stint covering Presidential politics. Rome chief? Campaign reporter? Not necessarily the expected C.V. of arguably the nation’s most influential food critic.

But who among us wouldn’t want to rip on rude service, overpriced desserts and the old-wine-bottle bait-and-switch?

Even when pleased, Mr. Bruni still gets in a few jabs: “Obviously, he didn’t like the color scheme, and he thinks fine dining should be loud—he said something like, ‘It was too quiet,’” noted Picholine chef Terrance Brennan, the surprised recent recipient of three stars.

Which makes Mr. Bruni’s pose as democrat of the dinner table appealing to many, just as it enrages others.

Food bloggers can’t help but cheer on Mr. Bruni. Eater.com conducts weekly “Brunibetting,” whereby contributors wager the score of the critic’s next target. And it has repeatedly posted “Wanted” posters bearing Mr. Bruni’s mug, along with the names of known dining companions, purportedly hung throughout the city’s kitchens.

Just this week, the blogs kvetched over restaurateur Keith McNally’s observation that Mr. Bruni has never awarded a female chef in Manhattan more than one star.

“When I’m sitting in a restaurant eating the food, the gender of the chef is not influencing how much I’m enjoying myself,” responded Mr. Bruni, who pointed to Brooklyn-based chef Anna Klinger’s two-star Al Di La as evidence of his own gender neutrality.

“If you fear critics, then he’s perhaps the most influential,” restaurant publicist Karine Bakhoum said of Mr. Bruni, whose scathing commentary sent one of her own culinary clients into DEFCON-5 full-scale-retaliation mode earlier this spring.

Jeffrey Chodorow’s highly ballyhooed and sword-adorned Kobe Club drew raves from Crain’s and Esquire magazine. But Mr. Bruni took exception to its “too many insipid or insulting dishes at prices that draw blood from anyone without a trust fund or an expense account,” awarding Mr. Chodorow not a single star.

An offended Mr. Chodorow fired back with a full-page advertisement, opposite The Times’ dining section, that accused Mr. Bruni of a personal vendetta and further questioned his culinary credentials. (Perhaps in testament to Mr. Bruni’s power of persuasion: Other critics who also panned Mr. Chodorow’s steakhouse—including New York’s Adam Platt and Steve Cuozzo of the New York Post—were spared the same paid rebuttal.)

While her client went on the attack, Ms. Bakhoum worked damage control, encouraging other food writers far and wide to come try Kobe Club for themselves, an effort she described as ongoing, even three months later. “Their responses have been unanimously positive, and we are continuing with this ‘judge for yourself’ campaign,” she said.

Despite all the fuss Mr. Bruni may have created at Kobe Club, Ms. Bakhoum downplayed the devastation of that single article. “I don’t think that any one newspaper has that much power anymore,” she said. “In the days when Mimi Sheraton was The Times’ critic, a bad review would close a restaurant.”

Not to diminish her own influence, however, Ms. Sheraton herself dismissed the notion of any reviewer ever holding such single-pen-stroke shuttering power.

Quite the contrary: “I have always said that more restaurants that I gave great reviews to have closed compared to those to which I had given bad reviews,” Ms. Sheraton told The Observer. “So, on the one hand, while a very bad review might not close a restaurant, a very good review might not assure continued success, even if it does in the first three months after the review.”

She added: “You have to ask the question, what makes the difference? And that has to do with the public’s reaction: If they like it and want to go there, they don’t care what anybody says. And if they don’t, they don’t care what anybody says.”

During her own tenure as The Times’ critic, from 1975 to 1984, Ms. Sheraton saw her fair share of restaurateur backlash, including several paid ads similar to Mr. Chodorow’s and even lawsuits—none of which ever made it to trial, she said.

“The worst thing they can do is tell more people about it than who knew about it in the first place,” she said. “That was what was so ridiculous about Chodorow’s ad. You know, he paid $40,000 to tell people that The New York Times hates his restaurant.”

Still, the retaliation is somewhat understandable. Even if a brutal review doesn’t bring down the house, that’s not to say there’s no immediate impact.

“Even the regulars at a restaurant might not go when there
’s a negative review, at least for a while,” Ms. Sheraton said. “It could mean they’re not sure of their own taste. But I also suspect that because there’s a lot of entertaining at these restaurants—business especially—no one wants to invite someone to a restaurant that just got a bad review.”

Naturally, the opposite is true for the eateries that pleasantly surprise Mr. Bruni.

Dan Barber, the owner of Blue Hill restaurant in Greenwich Village, described the impact of Mr. Bruni’s three-star review last August as “immediate.” “What we see generally after a good review like that: People are willing to come in earlier at the 6 o’clock tables, and people are willing to come in and eat later, which is a huge asset for us,” said Mr. Barber, now obviously a big fan of the Bruni Effect.

“One would think that with the rise of the Zagats, the rise of the blogs, and all the rest of the stuff that’s out there, that with Bruni, the power would be greatly muted. I haven’t seen that,” Mr. Barber added. “In fact, in some ways, it feels stronger than when [former Times critic] Ruth Reichl reviewed.”

Still, some restaurateurs seem entirely unaffected by reviews—even the deadly barbs of Mr. Bruni. Among the so-called “Bruni-proof” is the devoutly followed Mr. McNally, whose new eatery Morandi received just a single star last month. But just try getting a table.

“People don’t realize that neither Balthazar nor any of my restaurants ever received really good reviews. But they’re all still around and thankfully quite busy,” Mr. McNally said via e-mail. “I certainly don’t engage a P.R. person or anything like that. I simply try to make my restaurants the kinds of places that I’d like to go to. Nothing else. Hopefully, other people feel the same way.

“The smaller-minded critics, however (and this includes Bruni), don’t care for my places, because when they’re there, they feel disempowered. They don’t have the power, as they so often do, to alter the fate of the place. It drives them to distraction. But it only makes me smile.”