It would be nice to be able to add a definition to tags. I mean if you click on a tag it would say what the tag means and then have the results. Kind of like the tags on anidb.net Having the little bobble they have would be nice as well. I know it would be something I would use on my site.

I could understand tag categories like grouping names of television shows from other types of tags, but having descriptions would be very hard and long work for a forum to manage. Also after a while the descriptions could be very redundant.

Not how I look at it. It tags could be viewed and edited in the admin cp and a description be added from there it would save time.
Right now the tags use the search system which works but is not exactly how I want tags to work especially in the ip.content. In the forum and gallery that works fine but not in the ip.content.

For right now what I will do is create a dictionary page that lists tags and what they mean.