I now and then contribute to the wiki (account: Faf) and it is a bit of a pain in the proverbial butt.
The problem lies with "edit pending" messages. This is a problem in two ways:
- it is not very conductive to wiki'ing (you lose that immediate feel of "I contributed, whooo!")
- when you need to make an edit that requires multiple different actions (think: upload a picture, display it in an article) you need to wait for the approval of the former to perform the latter.
I guess the "edit pending" solution was implemented to fight spam, and I don't have much experience with managing wikis to propose alternative solutions (captchas? trusted accounts after a number of successfully reviewed edits?).