I've taken a pass over all of the current tags on this site and provided some wiki for many of those that were without any. Unless I missed one or two, I think every tag now has something. For a few, I didn't supply the extended version.
If someone is better at finding recent changes than I am, it might be worth a look to see if my additions can be improved. There were a couple that are a bit sketchy, and some that had inconsistent usage. For the latter I didn't try to write a wiki covering all questions, but considered the majority. This leaves some questions badly tagged, of course.