How many other people in their recommendations list do you either not know at all, or only know of them, but have never met? Whatever algorithms they use to pro

How many other people in their recommendations list do you either not know at all, or only know of them, but have never met? Whatever algorithms they use to produce these recommendations (your social graph, IP addresses in common, etc) will of course wind up surfacing a broad range of people, including some back you actually know.