I admit, I'm an organization freak. I have layers upon layers of directories to organize content on my computers that most would probably get a headache over. When I see people with 20+ files in a directory, I wonder how they can survive. Ok, maybe not that bad, but close. My blogroll is turning out to be just as bad. I have a lot of feeds I watch -- 148, to be exact, and a handful of these are aggregated feeds. Currently, Bloglines only allows you to add top-level directories. I want the ability to go deeper than that. Hell, even if it were only a second or third level, I'd be happy. My intentions aren't to test the limits, just organize my feeds.
When I consider my feeds, there are varying level of importance, which is how I group them. I have my main and casts groups for the main RSS and cast feeds that I skim thru briefly to pick and choose what I read; and then I have my "must read" and "spare time" groups that speak more to the level of importance the feeds are to me. Beyond that, I have two other groups of feeds which are even lower than the "spare time" group. Basically, I'd like to have more control over these groups without having 20 top-level groups. One nice feature is the ability to click on a group to read all posts in the feeds for the group. This is why I'd like the ability to group and read them hierarchically.