Quoted from MikeS:Silverball Chronicles is my favorite as they take a historical look at pinball. Reminds me of the old TOPcast podcast.
Slam Tilt podcast is another favorite that covers news, tech stuff, tournaments, etc.
Final Round is also good for competitive talk and modern game talk.
Loserkid and Super Awesome get the best interviews. Knock a few points off SA though for all of the annoying sound bytes/effects.
Yup, this was my list too. I like all but the super awesome IMO has too much editing and extra music and flare and it just seems to fluffed. But they have some good content.