The iOS version of Downcast is one of my most-used iPhone apps. Now there’s a companion Mac app, I’ll be listening to even more podcasts.
Josh Centers has a great review of the app over at TidBITS, if you’d like to find out more.
My thoughts? If you’re starting with nothing and want to get into the world of podcasting apps, try Instacast. If you’re a Downcast user — like me — and don’t want to migrate between apps, the Mac app is a nice addition, although there are some bugs in the 1.0 release (iCloud playlist syncing isn’t working quite right for me).