The whole concept is also important in social media. This is because people are forever using the search functions in sites like Twitter, Facebook and Linkedin. So you should always make a point of sprinkling relevant and popular keywords throughout your writing on these sites. Do that and you will be more findable by those searching within these sites for people to connect with. And because they are also indexed by Google, you might get some views via the search giant as well.
Linkedin in particular is loved by Google. So you should really take advantage of this and insert as many traffic drawing keywords in the various sections of your profile as spossible (without keyword stuffing, of course).