Bookmarks and watchpoints for selection and presentation of media streams

Selection and presentation of media streams, in which presentation is not limited by order imposed by the digital content representative of those media streams, in response to bookmarks and watchpoints settable and usable by a user. Bookmarks reference a location within the media stream, not necessarily pre-selected and possibly dynamically selected, in which a presentation can be started or restarted therefrom. Watchpoints reference a location within the media stream, or a presentation state for the media stream, in which an action can be triggered thereby. Bookmarks and watchpoints provide a general technique for presenting selections from media streams in response to metadata.