This happened in the last couple days (I was gone all weekend). Since I use a newsreader, this makes the RSS feed also hidden so I can’t use it in my reader, unless I go to the site and log in first.
I can’t duplicate the problem. Have you logged out and back in since I created the top-level categories?
I’m not sure exactly what the issue was but it has gone away now.
Almost certainly it was an artifact of my adding the top-level categories.