1. A system for generating an adaptive playlist on a computing device onboard a vehicle, the system comprising: an onboard vehicle computing device configured to execute a media player program, the media player program including: a media storage module configured to store a plurality of media items; a user preference module having user media preferences for a user; a contextual data module configured to receive in real-time, while the vehicle is moving, dynamic contextual data from an onboard vehicle data source, wherein the dynamic contextual data includes calendar information of the user received at the onboard vehicle data source from a user account at a remote data source via a wireless communication link, the calendar information comprising one or more of personal calendar entries of the user, shared calendar entries for a shared calendar to which the user subscribes, and synced calendar entries from a synced calendar maintained on a portable device associated with the user; and a playlist manager module including: a playlist generation engine configured to generate an adaptive playlist including a plurality of user playlist media items selected from the plurality of media items based on the user media preferences; and a contextual media selection engine configured to track and store the dynamic contextual data history over time, correlate the dynamic contextual data history with the user media preferences, select in real-time, while the vehicle is moving, one or more of contextual media items from the plurality of media items, based on the dynamic contextual data including the calendar information received at the onboard vehicle data source from the remote data source, and to interleave in real-time, while the vehicle is moving, the selected one or more contextual media items into and/or remove in real-time, while the vehicle is moving, the selected one or more contextual media items from the adaptive playlist.