IF THIS YEAR’S Sundance sensation, “Hustle & Flow,” is to live up to all the hype, it won’t be enough to generate millions of dollars at the box office. The movie has to generate millions of WOMPs.

A WOMP is a mechanism for measuring word of mouth. In the parlance of WOMMA (that’s the Word of Mouth Marketing Assn. to you and me), a WOMP is “a single unit of marketing-relevant information” passed from one consumer to another.

Let’s say I run into you in a bookstore and suggest you drop everything and see “Hustle & Flow.” Whether or not you follow my advice, you’ve officially been WOMPed.

I first heard about WOMPs last week at a WOMMA conference in Chicago. The event was called “Measuring Word of Mouth.” It drew some 200 ad buffs, market researchers and academics from as far away as Tokyo. The focus: evaluating the way goods get peddled in everyday conversation. As WOMMA chief exec Andy Sernovitz told me, “If a marketer says it, it’s an ad. If a real person says it, it’s word of mouth.”

WORD OF MOUTH marketing has been around for decades — think Tupperware parties and Avon Ladies. But it’s suddenly a red-hot field. As conventional advertising loses its clout, marketers are scrambling to infiltrate our day-to-day lives. They want to tap into blogs, Internet chatter and text messages, and also into off-line conversations among friends, colleagues and people who don’t even know each other — at parties, in church groups, you name it.

One WOMMA company, the Boston-based BzzAgent, has a network of 90,000 demographically diverse “brand evangelists” programmed to promote the company’s clients at every opportunity.

These volunteer BzzAgents don’t get paid. But if they fill out detailed BzzReports explaining who they WOMPed, they get free stuff like PlayStation games. Here’s how it works: If you hire BzzAgent to create a word of mouth campaign for your next novel, the company will send the book to a few thousand BzzAgents, along with a BzzKit explaining its various selling points. BzzAgent might charge you $100,000 for the whole campaign and generate 10,000 WOMPS.

Hence the importance of the WOM Terminology Framework, WOMMA’s new scheme for calibrating the effectiveness of word of mouth campaigns. WOMP isn’t part of the official WOMMA lexicon. The trade group prefers the terms WOMUnit, WOM episode or even WOM meme. But none of these, in my opinion, is quite as effective as WOMP.

THE BEST PRIMER on word of mouth marketing is New Yorker writer Malcolm Gladwell’s 2002 bestseller “The Tipping Point.”

Gladwell has two qualities rarely found in one person: the wide-ranging curiosity of a social scientist and a remarkably lucid prose style. “The Tipping Point” is about what he terms “social epidemics” — ideas, messages and products that spread like viruses, everything from Paul Revere’s historic call to arms on his midnight ride to a bestselling book, a brand of sneakers, crime statistics and STDs.

Like the WOMMA crowd, Gladwell has an Alfred Kinsey-like tendency to put human behavior into neat little boxes. Gladwell calls the people who spread social epidemics “mavens,” “connectors,” “innovators” and “salesmen.”

Turns out Gladwell is such a demigod in WOMMA circles that one person in Chicago, Max Kilger of Simmons Market Research, even taught a seminar comparing Gladwell’s mavens and innovators to the characters on “Gilligan’s Island.” According to Kilger, mavens resemble Mary Ann; innovators are more like the Skipper.

But for all its foibles, the science of word of mouth has clear applications for Hollywood.

Remember last year’s Sundance sensation, “Napoleon Dynamite”? Some of its success was the result of offbeat marketing gimmicks, like fan club contests and vintage “Vote for Pedro” T-shirts. But something happened to “Napoleon Dynamite” on its way to box office glory. The marketing dissipated and the movie became a bona fide word of mouth phenomenon.

“The idea of word of mouth is very Zen,” Sernovitz said. “You put the idea out there, let go, and if people like you and trust you, they’ll spread the word.”

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