In the very beginning, Yelp started as a service where we really didn't think people would write reviews for fun. The whole concept of user-generated content was pretty nascent in 2004.

One of the challenges of buying local advertising is, how do you know if it worked? How do you know if it's got value? We're moving toward an e-commerce experience for local, an Amazon-like experience for local.

When you read reviews on Yelp, you get a good sense of what's going to happen when you walk in the door of that business. The challenge is that there are fifteen million businesses in the U.S., and its very hard to communicate with all of them about how Yelp works, and why it works the way it does.

There's simply anger over the accountability that Yelp brings and also this feeling of powerlessness because so much power is now being put in the hands of the consumer. But the important thing that gets lost with some of these business owners who are very upset with us is it's the whole picture that counts.