1 Not that I am an expert but let me share.
2 It was so successful that all sorts of allegations were made about "brainwashing".
3 If you look at the most successful UGC site in the world, Facebook, it has been extraordinarily successful at converting lurkers into contributors.
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@likelink_kr: Amazon, Yelp, Foursquare 에 리뷰와 팁을 쓰는 동기가 무엇인가요? 라는 질문에 대한 마크 서스터의 답변 http://t.co/HE3SCIEY