Everyone likes a good podcast. iTunes doesn't make it easy to stay current, but Instacast does. It grabs those you already subscribe to, recommends new ones, and organizes them for easy listening at home or on the go.
WIRED Wonderfully simple interface lets you refresh all your 'casts with one tap.
TIRED Please, an iPad version for our beloved video podcasts! "Popular" list skews heavily toward nerdy Mac-related podcasts, but that might be more of a user base issue.