Systems and methods of presenting media objects are described. In one aspect, a group of media objects is selected from the collection based upon media object relevance to one or more data structures of a selected media file of indexed, temporally-ordered data structures. One or more of the selected media file and the media objects of the selected group are transmitted to a client for contemporaneous presentation at a selected summarization level. In another aspect, media objects in the collection are grouped into multiple clusters based upon one or more media object relevance criteria. The media object clusters are arranged into a hierarchy of two or more levels. A selected cluster is transmitted to a client for contemporaneous presentation at a selected summarization level.