“You have to make an environment that attracts the Justin McMurrys of the world, because that’s where the magic happens,” Mr. Studness said.

Natalie L. Petouhoff, an analyst at Forrester Research, said that online user groups conform to what she calls the 1-9-90 rule. About 1 percent of those in the community, she explained, are super-users who supply most of the best answers and commentary. An additional 9 percent are “responders” who mainly reply and rate Web posts, she said, and the other 90 percent are “readers” who primarily peruse and search the Web site for useful information.

“The 90 percent will come,” Ms. Petouhoff said, “if you have the 1 percent.”

Verizon explored the alternative of building the Web site and managing the forums itself, but it decided to call on outside expertise. Several suppliers, including HelpStream, Jive Software and Telligent, offer corporate social networking software with customer service features. Verizon chose Lithium Technologies, a fast-growing start-up based in Emeryville, Calif.

Lithium comes to online customer service from a heritage in gaming. Its chief executive and co-founder, Lyle Fong, was a founder of GX Media, which developed a leading Web site, Gamers.com, and created technologies for professional rankings and tournaments.

Lithium’s current roster of 125 clients includes AT&T, BT, iRobot, Linksys, Best Buy and Nintendo.

The mentality of super-users in online customer-service communities is similar to that of devout gamers, according to Mr. Fong. Lithium’s customer service sites for companies, for example, offer elaborate rating systems for contributors, with ranks, badges and “kudos counts.”

“That alone is addictive,” Mr. Fong said. “They are revered by their peers.”

Benchmark Capital, a venture capital firm that invested $12 million in Lithium last year, was impressed with the company’s gaming background and its focus on catering to super-users to build communities. Peter Fenton, a Benchmark general partner, said that many of the most popular consumer Web sites and services, from Wikipedia to Twitter, are animated by a relatively small percentage of avid users.

Image Credit... Mark Graham for The New York Times

“In customer service, it’s still very early, but I think it’s likely the same pattern will play out,” said Mr. Fenton, who serves on the boards of both Twitter and Yelp, a site where users post reviews of restaurants and other local businesses.