The enterprise social graph will likely outstrip the public social graph in both complexity and usefulness. It also will be easier to build because privacy is less a concern inside a company. The data that provides the evidence for the construction of the enterprise social graph can be used with far fewer restrictions. The Panama Canal was constructed by connecting lots of existing waterways and lakes. The enterprise social graph likely will be constructed in the same way, with many different data sets being mined to suggest relationships that can become part of the graph.
Source: forbes.com