NewsGator is re-architecting its Social Sites ESN (enterprise social networking) suite so that it can be installed independently of Microsoft's SharePoint collaboration server. The decision isn't terribly surprising, given that Microsoft last summer bought NewsGator competitor Yammer for $1.2 billion and has ambitious plans to deeply integrate Yammer with SharePoint and other Microsoft products, like Office and Dynamics CRM. However, this decision is a big technology and strategy shift for NewsGator.