Selecting popular content on online social networks

A social-networking system of an online social network, the system comprising:

• one or more processors;
• and a memory coupled to the processors comprising instructions executable by the processors, the processors operable when executing the instructions to:
• receive, at one or more of the social-networking systems from a client system of a first user of the online social network, a request to access a landing page of the online social network associated with the first user;
• access, by one or more of the social-networking systems, a social graph comprising a plurality of nodes and a plurality of edges connecting the nodes, each of one or more of the nodes being associated with one of a plurality of users of the online social network, each connection between two nodes representing a relationship between the two nodes and establishing a single degree of separation between the two nodes, wherein the first user is associated with a first node of the plurality of nodes;
• calculate, by one or more of the social-networking systems, a popularity value for each of a plurality of content objects retrieved from third party sources that are separate from and external to the online social network, each content object being associated with one or more second users of the online social network, the one or more second users being associated with one or more second nodes of the plurality of nodes, respectively, wherein the popularity value for each content object is based on an adoption of the content object by one or more third users of the online social network on one or more landing pages of the online social network associated with the respective one or more third users, the one or more third users being associated with one or more third nodes of the plurality of nodes, respectively, each third node being within a threshold degree of separation of the first node;
• select, by one or more of the social-networking systems, from the plurality of content objects based on their popularity values, one or more content objects to feature on the landing page of the online social network associated with the first user;
• and
• send, from one or more of the social-networking systems to the client system of the first user, instructions for presenting the landing page of the online social network associated with the first user, wherein the landing page comprises one or more of the selected content objects.