Facebook launched their third big offering, or that was what I was led to believe, last evening. A search function. With a weird name, "Graph Search". Now, according to the Business Insider who suggested that Facebook should have just called it "Facebook search", the term in tech world, social graph, refers to your network. Even Facebook network would or could have worked a bit better. If you are looking for the Facebook explanation, look no further: About Graph Search. As Paul said, this only works well if you make sure that your mates are active and you make sure that you are active. If you are active and post where you have been, what it was like, what you like, then one can get a better search result for all concerned.
But, don't take my word for how this function will be used, listen to the experts over at CNET -> Facebook takes on Google with Graph Search. And then there was another good one from PC Mag: Facebook Introduces Graph Search With Limited Rollout. I quite like that one paragraph, which shows the power of Facebook: "searches tap into the people, photos, places, and interests that populate those 1 trillion connections and 240 billion photos generated by Facebook's more than 1 billion users" 1 trillion connections? And you thought only Gideon Gono could count that far. Or the trillion Dollar coin idea, that was sent away in a rush!