The popular social networking site facebook is for more than just keeping in touch with friends and sharing photos, according to a new survey in the Harvard Business Review. Companies that use the popular social-media site and its fan page module to market themselves to customers can increase sales, word-of-mouth marketing and customer loyalty significantly among a subset of their customers, according to the new research from Rice University's Jones Graduate School of Business.

Researchers surveyed customers of Dessert Gallery (DG), a popular Houston-based café chain. Prior to the study, DG did not have a Facebook presence. Surveys of more than 1,700 respondents over a three-month period found that  the company's Facebook fans made 36 percent more visits to DG's stores each month, spent 45 percent more of their eating-out dollars at DG, spent 33 percent more at DG's stores, had 14 percent higher emotional attachment to the DG brand and had 41 percent greater psychological loyalty toward DG--compared to typical Dessert Gallery customers.

The authors say the results indicate that Facebook fan pages offer an effective and low-cost way of social-media marketing.

"We must be cautious in interpreting the study's results," co-author Utpal Dholakia said. "The fact that only about 5 percent of the firm's 13,000 customers became Facebook fans within three months indicates that Facebook fan pages may work best as niche marketing programs targeted to customers who regularly use Facebook. Social-media marketing must be employed judiciously with other types of marketing programs."

Facebook marketing programs may be especially effective for iconic brands, which appear to attract a higher percentage of their customer base as Facebook fans.