Dog-food sites shouldn't exist in a vacuum. There's a growing need to interact with other pet owners. The Cesar food brand Web site intent is to blur the lines between a brand Web site and the social Web. A big feature included here is a section on therapy dogs. Cesar targets small-dog owners who are in need of a better connection. But it's not just meant for other owners: Cesar has built an area where it can listen and respond regularly to consumers.