I think the big issue is what information is actually put into the thing. Most people look at it and go "hey, that's pretty cool," but that's it. They don't know what specific information needs to be put in the thing. If a list of wanted information is put up, perhaps it would make it build up quicker. I know, the idea is for it to grow as people come up with new information, but you have to start somewhere.
I suggest starting with the cold, vanilla Freespace information that I started (and stopped due to lack of time, energy and interest) some time ago. Litterally rip the information straight from the tables and post it (with explinations and the like). From there, we move on to modding, Freding, etc, etc.
The wiki login is confusing as well. Took me forever to figure it out.