A user may be looking for a podcast for a particular guest, and not necessarily a new show to listen to.

Allowing users to browse based on a particular guests will be great for they  can learn more about that person, and more easily follow their career.

On most podcast players, the show is usually what is most prominently displayed, and usually the easiest to search for.

Users will be able to click on the menu option that reveals the show notes, and as well as see what other shows that same guest has appeared on.