Allow users (with proper role) to tag other peoples' content

One of the biggest benefits to tagging content on a community site is that end users can organize content themselves (The forum software whose name escapes me, in use on wordpress.org has this). On one site I admin for example, crimethinc.net, certain users are very attentive to tagging and their content is more read, whether or not it's more relevant, interesting, etc. I think they'd be open to tagging other peoples' content, and I really don't have any problem with allowing them to, if it were implemented.

If it'd be better for me to make a forum post on the same subject, I'll do that.. I just figured that if I did someone would say, "Post a taxonomy feature request!" and well, I thought I'd do such first.