Products like Yammer allow organizations to offer employees Twitter-like and Facebook-like functionality in a workplace setting. They let employees set up profiles, do microblogging, participate in discussion forums and receive activity stream notifications about what their colleagues are doing.

The promise of such products is that they can improve the way employees communicate and collaborate by complementing e-mail, IM and other more traditional tools. The products can be integrated with other business applications and managed by the IT department.

Microsoft and other vendors selling collaboration stacks, like IBM and Cisco Systems, have been incorporating enterprise social networking (ESN) functionality into their products. Enterprise application vendors are doing likewise, including Salesforce.com, SAP and Oracle.

But Microsoft is behind competitors in building native ESN features into its products, said Gartner analyst Larry Cannell.

"Microsoft has the weakest social play in the market," he said. "With Yammer they would immediately become a very strong competitor in the social workplace."