The BBC's podcast directory has been updated. It's a huge improvement over the old one. Sarah Prag, who runs the Audio Services team that led the work, has written a post about it over at the BBC Internet blog. She explains the directory's new features better than I could so I suggest you read her post for the detail.
My favourite new feature is the ability to search by theme across all of the BBC's podcasts (this is how I know there are 68 news podcasts from all the BBC networks, 26 of which are from Radio 4). You might also like the way you can now sort podcasts by 'average duration' so you can match a podcast to the length of your commute, for instance (so now I know that the BBC's shortest podcast is Completely Burns from Radio Scotland - at one minute), or the really nifty Quick Find search function that locates podcasts as you type.
For the time being, the Radio 4 podcasts page remains the same but if you click through to an individual podcast's page (Broadcasting House, for instance) you'll find yourself in the new directory. Once you're there, click the big Podcasts banner at top left and you'll encounter the glories of the whole directory. In time, the new features of the directory will be added to the Radio 4 version. Bookmark the new version for direct access.
While you're there you'll probably learn that there are currently 45 Radio 4 podcasts, which makes Radio 4 the number one contributor of podcasts, just ahead of the World Service (with 41). I also learn that the top five Radio 4 podcasts are (in ascending order): In Our Time, From Our Own Correspondent, The Archers, Best of Today and at the top - by about a mile - Friday Night Comedy.