Hey, so it seems (<link) Wikia finally added a new user right, "Moderator", for forums/message walls; I have given you these rights on the Atelier 801 & Transformice Wiki (and only you *hint*). Interestingly enough however, this isn't set by default for anyone on current wikis, even Bureaucrats (I'm assuming new wikis will), so you may want to update your rights on wikis you're a Bureaucrat on (you can change it as a Bureaucrat, it's just not on by default).
Edit: they say admins can edit the group too, but apparently the change isn't live yet. Edit2: It seems admins can still do basically everything but remove a thread. I get it's meant for people who should have forum/wall rights but not admins and not really the other way around, but it seems kinda silly to me =p.