Dave Winer has brought up the idea of OPML reading lists and I was having a hard time following until I read this post by Michael Arrington.

Simply put, you will be able to subscribe to a blog reading list published by a trusted source. Or maybe a reading list group-published around a particular topic. It’s kind of like a blog-of-blogs (and I understand that feeds can be other things besides blogs).

Hmm. Could these reading lists be created like tag clouds in del.icio.us? Sort of social bookmarking a dynamic OPML list.