In parallel to the work that Dave has been doing, I'm working on a new feature for RCS: A page that lets you view an OPML file as an HTML directory.
Here's a sample directory. It's a rendering in RCS of the same directory that Dave linked to on Scripting News earlier today.
If you have an OPML file that you want to see rendered as a directory, go to this page, and enter its URL. Once released, any RCS will be able to render directories from OPML.
I'm also working on a way to add directories to a page on a Radio weblog. Here's a glimpse at the cutting-dege.
By the way, some Manila users will probably recognize this feature.