Buzz, a Python-based outline tool

Buzz is a Python-based outline tool that groks OPML.  I must say, though, that the home page for Buzz is one of the ugliest pages I've seen in a while.  (But it is cool: the page is a clickable outline.)  Installation looks like it might be a bit involved.  I'll probably try it, though; there's a dearth of tools that speak OPML.