EL PAYO I think the ability to manage podcasts is critical and can't believe that Apple left it out of iTunes.
Without Cast Away my podcast library would quickly balloon to many gigabytes (especially with video podcasts.) I may be a 'niche' user, but I find that the app has allowed me to subscribe to many more feeds than I'd otherwise have the time to manage manually, and as another reviewer has mentioned, the new 'caps' options keep both my iPod nano and my Mac from choking on too much input.
If you're trying to manage your podcasts video podcast subscriptions this is your app.
(Version 1.7.4)