As it turns out, 4ZzZ was having troubles with their podcast and live streaming but didn't discover this until the show was almost over. This is some of what I said.
Print-on-demand makes it easier to publish in smaller volumes, even though the production cost is higher per unit. This facilitates more innovation and more product choice.
Printed self-publishing isn't new, but POD allows people to print small volumes in sizes other than Letter and A4. Games discussed here included Don't Rest Your Head and Braunstein.
Publishing through PDF is a zero-cost production method, once development costs are recovered. I wish I'd mentioned the Free RPG Blog here.
Pricing for PDFs is wide and varied, from the expensive to the free. Games discussed: Houses of the Blooded, Dresden Files.
Bundles of book-plus-PDF are a great marketing exercise. Games discussed: A Penny For My Thoughts, and a plug for the Bits & Mortar Alliance.
PDF technology offers more than just a non-printed document. Linked text throughout the document is just one example. Games discussed: Happy Birthday Robot
Digital publishing is not limited to PDF. D&D Insider is an example of a specific application for the digital distribution of game rules and character creation. WOTC's move away from PDF to DDI is a way to guide people to WOTC content, without actually blocking third-party materials from being used in D&D. Games discussed: D&D.
The future of digital publishing is anyone's guess, but the untapped area is probably the realm of the app, especially the app that integrates rules, character generation, note taking and dice rolling. I couldn't remember the name of the iPad app at the time, but it's Dicebook.
Despite the availability of digital publishing, digital dice-rollers and apps for your smart-device-of-choice (including my confession as an Apple Hipster), the gameplay experience at the table isn't significantly altered. Minor changes are seen in the books we carry to the table, and perhaps the realisation that some players might be on twitter rather than checking a rule or engaging with the game. It's vital that in any RPG, the point is to engage in the social activity of story-making with the others at the table. Games discussed: None, but a big shoutout to Vincent Baker and his model of dice & clouds.
There you have it. We covered a lot, and thankfully it was more than print-vs-PDF.