What You Like

Search engines tamed the internet when they came out a decade ago, but Gen-Z surfers are growing up on social-networking sites like MySpace and LinkedIn. The advantage of these places is that they're at the same time vast and personal. According to market-research firm the Yankee Group, 13- to 17-year-olds are almost as likely to have visited a social-networking site in a given month as to have conducted a search. Need a yoga instructor? Ask your friends on Facebook. Looking for a pet groomer? MySpace will hook you up.

Entrepreneurs and Internet firms are trying to make this search for personalized information easier by extending the wiki model of collaboration. "If I'm looking for a movie, I want to know what movies my friends liked, and if I want to buy a sofa I'd rather buy it from a friend of a friend than a stranger," says Esther Dyson, a computer-industry analyst and investor. "The successor to Google is more likely to be Facebook than another search engine."

Hundreds of social search sites are groping for a winning formula, but none has been able to develop a critical mass of users. They range from shared bookmarking sites that let users "tag" content with descriptive labels to sites that use both humans and computers to sift information. At PreFound, users submit clusters of Web sites they think would appeal to like-minded people: a user looking for info on spas in California, for example, would get sites other users recommended—and as an incentive, the largest contributors get a slice of PreFound's advertising revenue.

Other services appeal to companies or individuals who want to build their own specialized engines. Searchles—a mash-up of the words "search" and "circles"—relies on networks of friends who share information. Users submit favorite Web pages and use tags to label them by category. When searching for tags, a user can focus on those contributed by friends, friends of friends or other groups he's joined. "There's a real utility in being exposed to people who aren't necessarily your closest circle of friends but aren't completely random, either," says Nicole Ellison, a media expert at Michigan State University.

Google recently launched Google Co-op, where users can build specialized search tools for specific subjects, such as health or videogames, based on users' favorite links. Over time, says Vish Makhijani, a senior VP at Yahoo Search, the integration of social media content with algorithmic search results will improve search "to deliver a more complete answer."

The ultimate goal is to combine the personalized information of, say, Facebook—knowledge of who your friends are and what they're clicking on—with the lightning-fast technology of the biggest search engines. That may be one reason why Microsoft announced last week that it is taking a stake in Facebook. The technology, though, isn't there quite yet, says Charlene Li, an analyst at Forrester Research. Social search engines still require users to do some work. For this reason, big search firms are likely to move slowly. "They won't integrate it into their overall algorithm until they know it really works," says Li. The danger, of course, lies in waiting for somebody else to get there first.