http://eater.com/archives/2011/07/20/yelp-accused-of-fivestar-review-extortion.php http://eater.com/archives/2011/07/20/yelp-accused-of-fivesta... http://www.e

http://eater.com/archives/2011/07/20/yelp-accused-of-fivestar-review-extortion.php http://eater.com/archives/2011/07/20/yelp-accused-of-fivesta... http://www.eastbayexpress.com/ebx/yelp-and-the-business-of-extortion-20/Content?oid=1176635 http://www.eastbayexpress.com/ebx/yelp-and-the-business-of-e... http://consumerist.com/2010/02/yelp-accused-of-more-negative-review-extortion.html http://consumerist.com/2010/02/yelp-accused-of-more-negative... http://jonathanturley.org/2010/02/27/yelp-accused-of-extortion-in-trading-positive-review-for-advertising-money/ http://jonathanturley.org/2010/02/27/yelp-accused-of-extorti... http://techcrunch.com/2010/03/04/yelp-lawsuit-extortion/ http://techcrunch.com/2010/03/04/yelp-lawsuit-extortion/ http://techcrunch.com/2010/03/17/complaints-against-yelps-extortion-practices-grow-louder/ http://techcrunch.com/2010/03/17/complaints-against-yelps-ex... http://www.pcworld.com/article/190231/yelp_hit_with_class_action_lawsuit.html http://www.pcworld.com/article/190231/yelp_hit_with_class_ac... http://www.wired.com/business/2010/04/yelp-fights-fraud-allegations-by-unfiltering-reviews-killing-pay-for-favorite-feature/ http://www.wired.com/business/2010/04/yelp-fights-fraud-alle... Yelp has a pretty shady history with this. The class action suit from a year or two ago was dismissed, so I assume what they are doing is legal in some sense.