For a medium that's supposed to represent choice, podcasting is rather restrictive. It's not quite "all or nothing" but it's close.
Today, when someone subscribes to a podcast, they have the choice of either listening from the most recent episode or backing up all the way to the first episode and start from there.
There isn't a third choice, unless you consider the painful attempt at self-selecting which episodes to download from crappy titles and missing descriptions inside an RSS feed a choice. It's really not.
Software can fix this problem, and I discuss it today on this short episode. I also talk about a dirty little secret of podcasting which you're probably not going to like very much. But that problem helps illustrate the problem if why podcasting needs to (and probably will) to better in the future.