There is this cat and mouse game that plays out over time where our team comes up with new and interesting ideas to identify content that we shouldn't recommend, and over time people are constantly probing that, trying to figure out how can they get around that and get a better reputation on Yelp.

Consumers are empowered by Yelp and tools like it: before, when they had a bad experience, they didn't have much recourse. They could fume, but often nothing else other than tell their friends.

You have to be very nimble and very open minded. Your success is going to be very dependent on how your adapt.

Everyone is panicked about the transition to mobile. I don't lose any sleep whatsoever.

Maintaining the trust of the consumer is critical to our business. We live and breathe only one thing, which is wanting to connect consumers with great local businesses, and I don't feel we can do that if we don't have effective ways to prevent gaming of the system.

If somebody writes a review of a dry cleaner, that piece of content is not wildly viral. It's not like a viral video that can spread across the world in a matter of minutes, so as a result, each market is almost an island unto itself.

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.