16. The method of claim 15 , wherein the advertisement is targeted to a user by utilizing information derived from at least one of an audio content item contained in a custom audio publication of the user, the custom audio publication template of the user, an audio content item and advertisement presentation history of the user, or a profile of the user; the history of the user indicating audio content items and advertisements previously presented to the user, audio content items and advertisements marked “tagged” by the user, and audio content items marked “tracked” by the user.
15. The method of claim 1 , further comprising selecting at least one audio and/or visual advertisement; and embedding scheduling details in audio publication metadata or audio content item metadata for the advertisement that is to be provided during presentation of the audio publication prior to or following presentation of the title segment, the summary segment, or the story body segment of an audio content item.