Salesforce.com, whose software helps corporate sales teams track customers and prospects, announced today that it is buying Buddy Media, which sells social marketing services. Salesforce will pay $689 million in cash and equity for the company, and it expects the deal to close in the third quarter.

Buddy Media, founded in 2007, helps such brands as Ford, Hewlett-Packard, L’Oreal and Mattel reach consumers on social networks, including Facebook, LinkedIn and Twitter.

The deal will enable Saleforce to combine its Radian6 social platform, which monitors conversations on social networks, with Buddy Media’s technology, Salesforce says. “Salesforce.com will deliver the first comprehensive marketing cloud that will allow customers to listen, engage, gain insight, publish, advertise and measure social marketing programs,” the company says in a statement. Client companies connect to Salesforce.com’s software via the web, hence the reference to its “marketing cloud.”

Buddy Media employs about 1,000 workers, writes Michael Lazerow, Buddy Media CEO and co-founder, in a blog posting. “Salesforce.com is welcoming all current Buddy Media employees, and the company is committed to continuing to invest in the Buddy Media business,” he writes. “Buddy Media plans to continue to innovate and build new product. We plan to build our sales team like crazy. And we plan to continue our global rollout, which is just starting.”