People influence people. Nothing influences people more than a recommendation from a trusted friend. A trusted referral influences people more than the best broadcast message. A trusted referral is the Holy Grail of advertising.

We help Chinese companies grow their customers abroad. They use Facebook ads to find more customers. For example, Lenovo used Facebook ads to sell its new phone. In China, I also see economic growth. We admire it.

If you're not doing something that people will remark on, then it's going to be hard to generate word of mouth.

Marketing is about values. It's a complicated and noisy world, and we're not going to get a chance to get people to remember much about us. No company is. So we have to be really clear about what we want them to know about us.

The marketplace is so important because we got to be in the consideration set. When somebody takes their phone out, and it's so easy to choose where you're going to go shop, if you don't have a really broad assortment, you're not even in the consideration set, and so that's one of the reasons why I was so convicted that we needed a marketplace all along, and others were too.

So growing ecommerce in the marketplace is key to being able to attract more advertisers. What we can do that some other people can't do is we can connect the dot between an ad you may have paid for digitally and a subsequent purchase in a physical store so that you can see the ad actually worked. So it too is an omni business for us.