Podcasting means recording an audio and playing it on your blog. Your blog readers, or in this case listeners, can listen at anytime by clicking on a link on your blog or download the file to their IPod or other MP3 player. The sound is usually excellent and as a listener there is not the buffering and re-buffering we experienced with early audio on the net.
Podcasting has been growing over the past few months and is really hitting main stream media. Yesterday Rush Limbaugh began offering a podcast of his radio show. California's Governor Arnold Schwartzenegger is now doing weekly podcasts. His site has a nice explanation of what podcasts are and how you can begin listening to them.
My guess is we will see podcasting continue to grow in main stream media in the coming months. This is fun to watch how technology is reshaping media.