Structure
Generally a podcast will consist of a series of posts in reverse chronological order. They may also have an about and/or a few other static pages. It is unlikely they will have a lot of static content or pages.
The Twenty Thirteen and Twenty Sixteen themes are good examples of themes suitable for podcasting.
Features
A podcast will have an audio file attached to each post or episode.
Glow Blogs automatically produce a RSS feed which listens can use to subscribe to a podcast.
Podcast content can easily be produced on computers, phones and tablets. Adding an audio file to a post automatically produces an audio player and adds the file as an enclosure to the feed. The Help Blog has a guide to posting audio quickly from mobile too: Mobile Podcasting.
The feeds produced by Glow Blogs work as podcast feed but can be enhanced so that the podcast can be submitted to iTunes. One way to do that is explained here: Getting a Glow Blog Podcast into iTunes.
Examples
Glow Cast is a site created as an example podcast, it is unusual as it has quite a few static pages providing help for podcasting with Glow.
Windscape is an audio book for pupils, each chapter in the book is an audio file recorded by the author. Given that this is not an ongoing production the home page uses the Display Posts plugin to provide a table of contents.