Online Networking Goes Small, and Sponsors Follow

MySpace used another data-mining technology, HyperTargeting, that sifts through its users' friends, comments and photos to fine-tune ad placement. That, too, has met with complaints from privacy advocates.

Faced with that sort of backlash, marketers are beginning to focus more on ads tailored to smaller, more specific audiences, said Jeremiah Owyang, a social-networking analyst at Forrester Research.

"Companies are learning that these smaller communities may reach people that are more valuable to their brands. It will someday feel more like information than marketing," he said.

Because members of niche social networks share common interests and experiences, they tend to spend more time on the site and contribute to the group by chatting and posting comments. Members tend to be less involved on bigger sites and are therefore less appealing to advertisers, said Julie Wittes Schlack, vice president of innovation and research at Communispace, an online consulting firm in Watertown, Mass.

"The bigger sites have become so cluttered and overrun with advertisers that members are used to tuning stuff out, even personalized ads," she said. But on networking sites that have a self-selecting demographic, people tend to trust the content, including ads, she said.

Facebook user Liz Collins, 26, of the District, said she's drawn to the smaller community aspect of social networking. She said she likes being able to join smaller groups within Facebook while still having access to all of her other friends. She recently joined YogaMates.com at the suggestion of a friend.

"It feels less commercial, which I like," she said of that site.

There's at least one social network for just about every interest or hobby. Yub.com is for shopoholics; Fuzzster.com is for pet lovers; OnLoq.com is for hip-hop fans; Jango.com lets music fans find others with similar tastes; and PassportStamp.com is one of several sites for avid travelers.

Some cater to the obscure. Passions Network, with 600,000 members, has 106 groups for specific interests, including "Star Trek" fans, truckers, atheists and people who are shy. The most popular group is a dating site for the overweight.

Membership on niche networking sites varies greatly, ranging from a few hundred to a few million. LinkExpats.com, which provides an online haven for U.S. expatriates, launched last month and has about 200 members. Flixster.com has 40 million members who rate movies and gossip about actors.

In September, Robin Wolaner launched a social network geared to people over 40 called TeeBeeDee.com, short for "to be determined." Wolaner, who founded Parenting magazine 20 years ago, said she saw a need for baby boomers who cringe at the thought of joining AARP. Next spring she plans to find advertisers targeting the middle-aged market.

"You've got a really active and hard-to-reach demographic coming to this site, and they'll all have to make difficult purchase decisions," such as life insurance and financial planning, said Wolaner, who runs the site from San Francisco. "If we are a safe and trusted place, they'll come to us when they make these purchases -- that's more interesting than just pure advertising."

But not all niche networks embrace marketers.

Sermo.com, a social network for physicians, rejected advertising out of concern that it would tarnish the site's credibility. Instead, Sermo sells access to the site to health-care-related companies wanting to tap into the community's specialized expertise. Sermo has strict membership rules and lets doctors discuss patients or medical opinions anonymously. Industry groups and drug companies pay top dollar for feedback from Sermo's 41,000 members, said founder Daniel Palestrant.

Zolve.com, a two-month-old network for real estate agents, is waiting to accept advertising until its membership, currently 4,200, grows. Eventually, Brian Wilson, its founder, hopes the members will help create detailed Web pages about cities and neighborhoods, making it an attractive place for local businesses to advertise.

"We want to gain their trust before we try to capitalize on them," he said.

Smaller sites still need to take care not to fall into the same trap as their bigger rivals; members may feel exploited if the sites are suddenly overrun with ads, said eMarketer senior analyst Debra Aho Williamson.

"The biggest hurdle is getting consumers used to the idea of being targeted," she said.