A social network can be considered as a country on a map. Then we can map diffrent countries and their residents and prepare a world map out of it. Residents of differenct countries can get informations about other countries, their people(profiles), communities(eg. facebook groups, linkedin groups), events, trending topics in other country(social network) .
Have a look at Gnip or Datasift. They do social media data aggregation. Recently, Twitter acquired Gnip.
What's the framework that you are going to use? What tools, language, etc?
I have something that I could add to this.
Actually i am newbie to big data. I just had an idea about this concept. I have not decided to use any framework or language. Maybe we can discuss and take it forward :)
Okay, I have been working on an application of game theory to social networks. Will be happy to discuss it.