So, I got the notice over on the main site about how the new tagging system will work. While I think the whole thing is a good idea, I do have a suggestion related to that second change, the one about users putting tags on others' work: why not just run the new tags by the poster of the submission? This way, the moderators and admins wouldn't have to worry about users having problems with new tags, and each user could decide for themselves whether or not they want to keep the newly suggested tags.
All the same, it is a good update; glad the site is being kept fresh!