‘ve seen hundreds of these posts, and the reason is that, even with all the power of Google, there are just some things that your friends know better. They know your tastes, your budget, and they might have experiences that are similar to your own. And, if they use Facebook a lot, they might have at some point “liked” a book they read, recommended a doctor, or checked in at a pub in London. That data is there, but without a search tool, it was hard to access. That’s why people posted these queries, hoping people would see them and respond. (via Facebook’s Graph Could Be OkCupid, Yelp, and LinkedIn, All in One - Rebecca J. Rosen - The Atlantic)