Social networks and other interactive sites where people share information will become integral parts of corporate marketing campaigns in the next several years.

While this observation may not seem startling, it suggests a powerful transformation in how people buy and the way companies sell. "I see marketing changing considerably," said Pauline Ores, senior marketing manager at IBM.

Ores, who spoke Wednesday at the Search Engine Strategies conference in San Jose, said companies such as IBM are already urging users to comment on products, such as customer-relationship-management software. Their comments, posted on a social-networking page on the IBM site, can influence future product development.

But the impact of social media will go much deeper, said Erik Qualman, a global vice president at EF Education. In two to three years, content on social networking and other social-media sites will be searched by search engines and provide a new channel of information to users.

People looking for new cars will know which of their friends have the same cars and will be able to read their friend's reviews, Qualman said. Companies will offer customers marketing dollars to post the reviews, he added - hopefully without influencing what they review will say.

"Post what you want (and) we'll pay you," he suggested a corporate marketing program might offer.

"Social media is just interaction and it's only going to increase," said Brent Csutoras, an online marketing consultant also at the conference. "Search engines will pick up much more."

At the same time, companies will mine the data they collect on the social-networking pages they put on their own sites. When an educational travel company such as EF notices a lot of people posting comments about a trip to Costa Rica, they will put up more information about future trips to the country, he said.

By Mark Boslet, Editor at large.