Back in 2012, we launched the Structured Tag Cleanup Initiative (STCI). It was very successful in identifying tags to create, merge, remove, and blacklist. However, it has been about 3 years since this effort was launched, and I think that it's time to relaunch this campaign.
The process will be very similar to the last effort:
Identify a tag that has issues. This may be a tag that should be deleted and blacklisted, or two or more tags that need to be merged or made synonyms of each other. As these tags are identified, post an answer in this question. If you think that a multi-way merge is necessary (for example, someone identified that tag X and Y should be merged, and you feel that tag Z should also be part of this merge), edit the existing answer.
Vote on candidate actions. Using the comment feature, comment on the proposed actions. Up or down vote as well. I hope to take the next 2-3 weeks to gather a list of actions and then treat this question as a queue. Starting in May 1, I'll accept the top voted question and that will mark the cleanup action. After completing the action, I'll delete the answer and accept the next one. Note that at the very end of the initiative, I'll undelete all of the answers and close the question for historical reasons.
Execute the cleanup. Review the questions in the tag. Vote on the question and answers, make edits to improve them, edit the tag wikis, flag for immediate moderator attention or for moderator actions, and otherwise improve that corner of the site. Each cleanup will likely last 1-2 weeks, depending on the size of the tag. Please try to avoid flooding the homepage with edits. If there are a large number of questions that require edits, the window for a particular tag may be longer.
Feedback. After a few cleanups, we'll review the process and how we're doing and prioritize the work going forward.