Apple’s iTunes is now poised to take over the world of podcasting the way it took over song downloads. There’s just no easier tool for finding and subscribing to your favorite audio shows, both pro and amateur. So far iTunes has about 3,000 regular podcasts, all of them free for you to download and listen to at your leisure. A few that have caught my ear so far: The Rock and Roll Geek Show (new indie rock), Pop Culture Rant (what it sounds like, from an opinionated Noo Yawker), The Delta Park Project (pop culture and comedy bits), Cinema Playground (movie trivia), and Firesign Theatre (new and old bits from the venerable comedy troupe). Go, browse, and return here with your recommendations. (Warning: some language may be PG-13- or R-rated.)