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 Yelp first took off, our rankings on Google would fluctuate wildly.

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.

The biggest thing is to create a product that consumers find useful. As more and more people like something, it becomes harder and harder to have a conspiracy theory about it.

Choose something you are passionate about - or a pain point that has affected you and that you feel really needs to be changed.

I think with every successful consumer Internet business, there will be lawyers that are interested in going after your company, especially when they think that there's a financial incentive.

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.

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

About every year or two, there is a moment of truth where there's some new development in the marketplace, some new technology, some sort of existential crisis. You just have to be vigilant about looking out for those moments.

Theres 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 its the whole picture that counts.

Yelp is in a very nice spot: local data, and especially review data, is one of the killer apps on mobile phones.

There are so many businesses that are succeeding on Yelp that don't pay us a dollar, and we're really excited about that.

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.

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