The Long Version: As defined bPodcasts were originally online audio broadcasts available for streaming and or downloading (wherever available), hence the name iPod Broadcast. By this definition, the original Podcasts were in essence Spiritual Successors
to Radios, except while radios broadcast on air, Podcasts are broadcast online. Several modern day radio stations were also made available to subscribers, which mirrors that of today's podcast viewers. Additionally, a lot of radio stations offer podcasts as available downloads and even though podcasts have since included video, the same principle of "tuning into/ downloading" certain podcasts has remained the same.
The Laconic Version: OK, so its not much, but we need padding for this new subthread and with only a few existing Podcast threads out there, everyone was on board. So we branched out and made this the Unofficial Podcast Subforum. And theres also quite a bit of overlap between the two.