Microsoft accidentally (or maybe not!) leaked their own social networking platform codenamed Socl a while ago.
The company has revealed some more information through The Verge network.
The service is similar in nature to Google Plus and Facebook. Microsoft is a close partner and investor in Facebook but they surely want to have their own thing in the social networking space.
It is pretty clear from the recent developments at Google+ and Facebook that these networks are becoming an identity service rather than a social networking one.
Microsoft Socl remains a research project for now but it is pretty clear that the company is soon going to compete with their own partner Facebook in this space.