I think Podcasts are a pretty interesting thing. There's several I subscribe to ranging from local music shows to cult movie shows to video Podcasts of all manner. I'd like to throw out a little constructive criticism to anyone doing one of these things, so here goes.
First off, I'm not expecting professional quality but at least get everyone talking on a mic. And try to match the levels somewhat. There usually seems to be one person substantially louder than all the others (and it's usually the person who talks the most) and it becomes very difficult to hear what anyone else is saying.
Go easy with the sound effects. It's a Podcast, not America's Funniest Home Videos. I'd say the same for music, unless it's a music Podcast. And, back to the sound balance, don't let the music drown out anyone talking.
The biggest beef I have is people need to spend some time editing once they are done recording, especially if you are using Skype, which seems to drop out a lot. There is nothing more boring than listening to five minutes of "are you there? I think we just lost so and so" twice an episode.
Speaking of editing, it seems like all the Podcasts I subscribe too keep getting longer and longer. If you can't keep it under an hour, break it up into two episodes. (Honestly though, an hour is really pushing it, as far as length goes.) Again, there's usually a lot of fat to be cut, places where the conversation rambles, inside jokes, etc.