One of the neat things I've noticed on del.icio.us lately is when tagging a
site (using it's posting bookmark or popup), it displays all your tags, plus
"popular" tags for the site, and "recommended" tags from th site. The
recommended tags seem to be coming from the metadata on the page, while the
popular tags seem to be coming from others who have bookmarked the same
site. You can choose from the recommended tags, popular tags, your own, or
make up some new ones.
I can definitely see this working for catalog systems, and having all the
benefits of moving towards more usable terminology. I can definitely see
this working for the user experience, also (in fact, that is probably the
best place for it, but it would be a shame to just leave it there and not
use the consensus that would emerge on tags for items) There have been
times when the tags displayed for a site were "correct" but they were not
what *I* wanted, to be able to find the site again.