Microsoft is reportedly set to acquire the Yammer business social network for an estimated $1 billion. The deal would give a much-needed social network injection to its SharePoint business collaboration platform. Yammer - with an estimated valuation of $500 million - makes business-oriented social network tools for internal company sharing and discussion centered on blog posts and automatically generated content (such as notifications that a document is ready to edit or a sale has been closed). The companies aren't talking, but this kind of software should be highly attractive for Microsoft, as it tries to move from being perceived as an old-school desktop software provider to being the source of modern, connected, social-media-aware solutions. SharePoint Is the Key One key to that transition is the company’s flagship corporate collaboration platform SharePoint.