Another update on Wiki status
It WILL be a mess when it opens up. In fact, I'm going to go so far as to say that you should not rely on it for most editing purposes. When I open it up, I would like to request that all regular wiki editors help pitch in and get accurate information on everything on the Things, Sectors, and Linedefs lists. That will be the biggest priority come opening. If those are fixed up, then all the other tutorials that need correcting and referencing will be MUCH easier to fix. I guarantee it.
So, expect a mess, and don't take everything the pages say as exactly how anything works. Much of the material is undocumented.