Podlog is a podcast directory based in the UK.
It uses a two level hierarchy of topic categories. There's an "English" directory, and an "international" one. The international directory has a LOT more listings.
It would help for them to have more subcategories, because the category lists are a bit long.
A show listing contains the show description, and a listing of the episodes, with episode descriptions. There is an embedded media player put on each page.