Wordpress 2.2 will have both categories and tags.
Currently wordpress users either use categories as tags, or install an external tagging plugin, or don't tag.
With 2.2 you can put a post in category Computers->Internet, and tag it yedda, knowledge, sharing, questions, saja, tzafrir.
See the difference?
For more wordpress discussion you can hang around the wordpress forums and the wordpress irc channel: #wordpress on irc.freenode.net
