“LTHForum,” his customers told him.

To which Carroll responded: “LTH what?”

Carroll quickly became familiar with LTHForum.com. Since food enthusiast Gary Wiviott started the message board in 2004, it has gained steam in the local restaurant world, and now wields the power to make or break a business once held by newspaper critics.

Wiviott calls the site a “discussion board,” and says that “when you post something on LTHForum, you better be prepared to defend it” to the rest of the community (many of whom chime in within minutes). The site is primarily filled with amateur opinions about restaurants, and the discussions that evolve from each post ensure the opinions always stay relevant: Thanks to a bottomless capacity for continuing the conversation, a simple announcement about a restaurant opening can turn into a yearlong argument. (Just check out the thread about Irving Park barbecue joint Smoque.)

But if LTHers aren’t technically critics—they have no credentials or editors, and aren’t shy about announcing themselves in restaurants (look for the guy taking pictures of his food)—their influence is still hard to ignore. It’s not just restaurant enthusiasts who are reading LTH; the food media are frequent users. Wiviott is a personal friend and eating partner of The Reader’s Mike Sula, and other local food writers, such as the Tribune’s Bill Daley, often post on LTH to solicit opinions. Even food writers who aren’t as open about their relationship with LTH would be hard-pressed to declare they had never been tipped off by the site, where they often discover restaurants and dishes that find their way into articles.

Of course, with its influence being so hard to track, it’s impossible to know how much impact LTH has. And that’s a drawback that may function as its glass ceiling. When Alberto Ramos was asked about LTH’s influence on his restaurant El Cubanito (first written about on LTH in December, viewed more than 1,500 times and picked up by almost every media outlet), he was perplexed.

“LTHForum?” he asked. “Never heard of it.”