This is a bit odd... Since hitting the 10K rep, I've tried to help out the mods with edit approvals and the like and that appears to include tag wiki edits. The odd thing is, I don't have normal editing capability for tag wiki. This strikes me as an odd hole in the process... I can approve edits but can't make them? Any ideas?
Correct, this is by-design.
At 10k we ensure at least 2 people look at the tag wiki edit (the editor and suggester)
At 20k we allow you to edit whatever you want
The idea is that we want more people looking at the wikis cause they are so prominent on the site.
Besides, we need to be able to give you something at 20k :)