Other people though... part of it could be that they'd rather have someone they know and trust run it (enough fan sites out there have started out by good intentioned people who then reach the end of their rope and close it down. I noticed that there's a not on the wiki against that, but still, in general), but it could also be that a wiki is only as good as the people putting effort into it, and they feel that the OTW will have a big enough following to make their wiki better, simply because that's something that they could help with and say they were an active part of OTW.
... hmm, I'm doing a really bad job explaining in words what I mean here. Really, bad. It's... I also think that the fact that something already exists isn't enough of an excuse to the members of the OTW not to make another one, because there are already things out there for all of the projects they'd like to make. There are already quite a few multi fandom archives, that many people totally love, and feel insulted that anyone would try to replace, there are already social networking sites out there (so, so many), I'm sure there's already groups out there trying to document fannish history (I know there was a fairly comprehensive list of the HP fandom in the earlier years out there somewhere), and I *know* there are already people out there looking into the legalities of fandom in general. Just because something already exists doesn't mean that the OTW can't make another. And even if the other alternative out there is a *good* one, the OTW wants to present an "all in one" feel for newcomers to fandom, and to fandom as a whole. Someone who's been in fandom for a while, or who has taken the time already to look for a wiki might see the one you linked to, but many others have no idea of it's existence. They want to have one that's right there in a central location.
And I don't think the OTW is going to go looking for affiliates, at least not anywhere near the beginning, because it opens up a whole *other* can of worms (why did you choose one over the other? And the fans/users of the "other" might come to resent the OTW for not choosing them, while they still have to deal with the one they choose, and all the expectations of the existing users, as well and their rules and how they fit into the OTWs rules). I do have to wonder though, if the owner of that wiki were to speak to the OTW and offer up her wiki to be the OTW wiki if they wouldn't take her up on it, I don't know, but it does sound like a much easier solution to me.

I should point out I'm still not decided one way or the other how I feel about OTW.
Yeah, I was decided, but it really does depend on how things turn out. They can still screw us up yet :P

Gah! I just can't shut up it seems, sorry for the hugely long repsonse....