Fan inspired wikis are nothing short of amazing works. I got lost in a few of them.
Memory Alpha is the wikipedia for the Star Trek television programs and the animated series.
The members of this wiki have decided that only material that originated from the television and animated series could be considered for inclusion on this wiki. This is referred to as the canon.
That means no fan based fiction, audio books, new characters derived from comic books, video games or graphic novels can be included. For that type of information you have to go to Memory Beta.
For Star Wars fans there is the fan based Wookieepedia http://starwars.wikia.com/wiki/Wookieepedia and the official Databank wiki at http://starwars.wikia.com/wiki/Databank
There are lessons that can be learned from these sites. First of all the community is very protective of the information that goes into the wiki. You don't want to be the person posting bad info. They will find you. Quickly. It would not be pretty.
The information has to be verified, meaning you have to state your source. There is a huge printed catalog of books that document Star Trek and Star Wars mythologies, ships, engineering, languages (Klingon) and costumes. Knowing it is not enough. You have to document your article or it might be removed for incompleteness.
Finally everybody has to play nice or you get kicked off the wiki. You won't find much troll or crude content. It is a protected place.
These are some of the lessons that I hope Wikipedia can convince its many users to adopt with the same level of vigilance.