Now that I've subscribed to the show, it is showing up in the My Podcasts section of the Podcasts app and still, everything is working as expected. This is why I suggested earlier that you should delete the subscription, kill the app, relaunch the app and then resubscribe. It's possible that the app has "cached" something from when the feed wasn't working. The only thing I can think of beyond that is that you might be behind a firewall or some other proxy that's blocking the download. It's really strange.