A nice article in D-Lib Magazine : Tidying up Tags? I admit that I didn’t read it, but it is related to the problem that I don’t really “use” tags. As the number of post is increasing, I don’t get much better search capability or organisation with tags.
There is still a lack of intelligent tools to manage tags !
Besides, with microformat, the tags could be embended into the post, avoiding external tools like Ultimate Tag Warrior. If the search engines (Google, Yahoo …) could catch up on microformat, you could said bye bye to all the tag stuff. Precisely, the tag would be just some words of you post marked as microformat (authors, subject, keyword, ISBN, movie title …)