I’ve been using Instacast to subscribe and listen to podcasts since I first came across it over a year ago. It’s simply a great app and version 2 has a lot of design and functionality improvements — I like how Stephen Hackett describes it as the best getting better.
Thanks to apps like Instacast and Rdio, the native Music app on my iPhone pretty much never gets used. Instacast 2 is just a buck in the app store.