As traditional broadcasters begin experimenting with podcasting I see the power of main stream media being placed into the hands of individuals. Bloggers realized that you don't have to have a newspaper press to make news and now people have realized you don't need a radio station to broadcast your ideas. It won't be long before people realize that you don't need a TV station to produce video content.With this in mind I started thinking about how to extend the power of the medium beyond just audio. I came up with a simple extension to RSS that can be used to enable media-centric podcasts.
<item>
<title>Raizlabs Audio Blog</title>
<link>http://podcast.raizlabs.com/sample.mp3</link>
<description>Example showing how you would add notes to a podcast</description>
<enclosure url="http://podcast.raizlabs.com/10.20.2005.mp3 " length="15893494"
type="audio/mpeg">
<a timestamp="4:10" href="http://www.raizlabs.com">
Visit our website to learn more</a>
<a timestamp="6:32" href="http://www.apple.com/itunes">
Download the new itunes</a>
<img timestamp="7:45" duration="1:00"
href="www.raizlabs.com/image.gif">
</enclosure>
</item>
I've taken the enclosure tag and extended the concept so that the enclosure can contain additional resources. Media such as images, links and potentially text and other resources can be synced in time with a podcast. I call it "hyp-casting" or hypercasting. The broadcaster is pushing links and images at the listener allowing them to follow along either directly from their web-browser.
Footnote: It seems that apple already has something like this. In their release of Itunes 4.9 they have something they call enhanced podcasts. The details should be available in the apple podcast specification. It seems that they embed the meta-data inside the audio file.