1. A method comprising, by one or more computing systems: receiving at a social-networking system from a video-content-provider system a request comprising a user identifier associated with a user of the social-networking system; querying a social graph of the social-networking system for stories generated by one or more connections of the user on the social-networking system, the social graph comprising a plurality of nodes and edges connecting the nodes, the nodes comprising user nodes that are each associated with a particular user of the social-networking system, wherein edges between the user nodes identify relationships between the users of the social-networking system; sending one or more of the stories from the social-networking system for use in connection with a service provided to the user by the video-content provider; receiving, at the social-networking system from the video-content provider, an indication that the user has selected a user interface element to post a new story on the social-networking system that indicates that the user is currently watching particular content, the user interface element being displayed along with the particular content being watched; creating, by the social-networking system, a new edge in the social graph between a user node associated with the user and a content node associated with the particular content that the user is currently watching; receiving, at the social-networking system from the video-content provider, an indication that the user has selected an option to passively share what the user watches in the future without any further explicit action from the user; and automatically posting, by the social-networking system after receiving the indication that the user has selected the option to passively share what the user watches in the future, new stories on the social-networking system as the user watches new content, each new story comprising an indication of the particular new content being watched by the user, wherein the new stories are automatically posted on the social-networking system only if the user has continuously watched the new content longer than a predetermined amount of time.