This video from Meta Brown, (@metabrown312 on Tweeter), a marketer who focuses on advanced analytics, is a nice high-level overview of Netflix recommendation algorithm.
Summary: How Netflix knows what videos you will like. A reply to a blog post by film critic Amy Biancolli of the Houston Chronicle's entertainment blog, Peep. Explains, at a "no previous experience required" level, the method that Netflix uses to select video recommendations, collaborative filtering.