In seeking to bolster its social credentials, Microsoft is reportedly on the brink of acquiring online networking company Yammer — in a deal potentially worth over $1 billion. Yammer is used primarily as a tool for group communication and collaboration within companies and started off life looking very much like an early version of Facebook. Unlike Mark Zuckerberg's creation, however, Yammer proudly proclaims itself "the enterprise social network" and offers no pretense of competing in the casual socialization stakes. Current reports suggest that a deal between Microsoft and Yammer could be sealed as soon as this Friday, with Bloomberg's unnamed source indicating that the price could be above the billion dollar mark.