1. A system for identifying relevant feed items to display in a feed of an enterprise social networking system, the system comprising: a database system implemented using a server system comprising one or more processors, the database system configured to cause: identifying from a plurality of data sources associated with an enterprise social networking system: a first subset of data items as having a first characteristic satisfying a first relevance parameter indicating relevance to a user of the enterprise social networking system, the first relevance parameter identifying an inner circle of data sources as a subset of the data sources with which the user interacts at or exceeding a user-designated frequency, a second subset of data items as having a second characteristic satisfying a second relevance parameter indicating relevance to the user, the second relevance parameter defined by an interest graph associated with the user, the interest graph maintained as a data structure using one or more data objects in a database to identify topics, feed items and keywords designated as being of interest to the user, and a third subset of data items as having a third characteristic satisfying a third relevance parameter indicating relevance to the user, the third relevance parameter identifying a group or an organization with which the user is associated; displaying a highlights feed on a display device, the displayed highlights feed comprising a plurality of channels, each channel graphically identified as associated with a respective relevance parameter, the channels comprising a first channel defined by the first subset of data items, a second channel defined by the second subset of data items, and a third channel defined by the third subset of data items; updating the interest graph associated with the user based on user input corresponding to user activity with respect to one or more of the plurality of data sources, the updating of the interest graph comprising updating the one or more data objects in the database; updating the second characteristic based on the updated interest graph; updating the highlights feed according to the updated characteristic; identifying a further data source based on an analysis of a combination of the updated interest graph with one or more of a social graph associated with the user or a sentiment graph associated with a user; generating a recommendation of the further data source as being relevant to the user; and sending the recommendation to a computing device associated with the user.