1. A tangible computer readable medium storing a computer program executable by a processor, the computer program producing a user interface of a social interest estimation system, the user interface comprising: a social interest heat map area for displaying a social interest heat map showing levels of social interest for a plurality of events corresponding to a series of chronological time segments in a time-based medium; a media display area, visually distinguished from and concurrently displayed with the social interest heat map area, for displaying an event selected from the social interest heat map; and a social media display area, visually distinguished from and concurrently displayed with the social interest heat map and media display areas, for displaying a plurality of social media content items relevant to the selected event, the social media content items authored by users of a social networking system.