Think of them as digital water coolers—surrounded by thousands of workers engaged in serious business conversations.

Do business and socializing mix?

Apparently so. As the number of business users of social networks continues to increase, advertising expenditures will rise, too. In the US this year, advertisers will spend $40 million to reach a business audience on online social networks, and that is just the beginning. According to eMarketer projections, that ad spending will reach $210 million in 2012.

“As compelling as the ad growth is, marketers will spend far more over the next few years to create and manage their own social networks for business customers, partners, suppliers and vendors,” says Debra Aho Williamson, senior analyst at eMarketer and author of the new report, B2B Marketing on Social Networks: Engaging the Business Audience. “These business networks will serve a range of purposes, from improving customer communication and collaboration to aiding product development.”

A clear sign of the revolution in business thinking and behavior is the popularity of LinkedIn—the most widely known professional social network—where the audience has more than doubled in the past year, and the rise of additional business-oriented networks, including a raft of networks aimed at verticals.

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To find out more about eMarketer report ‘B2B Marketing on Social Networks: Engaging the Business Audience’, click here