If you have a successful wiki, watch for Wikipedia creep. It's easy to spot. One day, you have a nice and happy community. Suddenly you have an argumentative, irritable and negative community. What happened? Likely those in Wikipedia who didn't make the admin cut or get accepted as authors there have found your little wiki a friendlier corner with better administrator prospects than Wikipedia ever offered. And likely they turned up with baggage in hand, ready to offload some of the less desirable Wikipedian elements into your community.

If this isn't stemmed at the point of its occurrence, you will end up with a large change of outlook on your wiki as it morphs more and more into a mini-Wikipedia, with similar outlooks, lack of flexibility and top-heavy bossiness. Jump on it and root it out before it strangles.

Signs to look for include watching out for a rash of grammatical fantacism by editors who never write; a rash of template creation to overhaul existing templates that were working perfectly well before; more arguing on forums than actually editing; disrespectful language; and admins not behaving supportively of one another.

Yes. There's a wiki out there right now undergoing the WP transformation.