The number one skill of a Social Seller is listening. Listening to conversations that are relevant to her company and clients; Listening for conversations about people and companies talking about their problems; Listening to understand your buyers better.
LinkedIn is powerful resource for listening and learning. People at all levels of companies now have profiles where you can learn a great deal about them before your even call on them; Many companies have set up Business Profile pages where you can see the employees who work there; All this linked by by mutual connections: The people you're connected to who can introduce you to people you want to be connected to. Take a look at the Anatomy of a Social Seller for tips on how to master this skill: