This seems like they paid people to write reviews, but I see no suggestion that they instructed paid reviewers to be biased. More content is better for everyone, as far as I can tell.
Another Register article (http://www.theregister.co.uk/2009/02/19/yelp_pitch_revisited...) seems to be at most an accusation of unethical ad sales tactics, and it includes the CEO flat-out denying that they'd ever manipulated reviews for money.
This seems like they paid people to write reviews, but I see no suggestion that they instructed paid reviewers to be biased. More content is better for everyone, as far as I can tell.
Another Register article (http://www.theregister.co.uk/2009/02/19/yelp_pitch_revisited...) seems to be at most an accusation of unethical ad sales tactics, and it includes the CEO flat-out denying that they'd ever manipulated reviews for money.