I wouldn't give Yelp too much praise. It's been alleged that Yelp engages in astroturfing and unfair business practices[0], and the documentary "Billion Dollar Bully"[1] even accuses them of "Mob-Like Behavior".
Oh definitely - I can't say that I've had stellar experiences with Yelp in the past for restaurants, barbers, etc, from the consumer side, and I hear it is much worse as a business. I was just very surprised that in this niche Google performed so poorly and Yelp so well. I wouldn't go on to generalize from this experience though.