User blog comment:Norleon/KyotoAnimation-anime-wikis united/@comment-24162773-20140602211701

Current status: There are 9 wikis willing to participate (Haruhi, Kanon, Chuunibyou, Free!, Kyoukai no Kanata, K-ON!, Hyouka, Nichijou, Amagi B.P.). Thus we need 6 more for the full number: Full Metal Panic, Air, Lucky Star, Clannad, Munto, and Tamako Market.

So we have 5 KyoAni wikis on the bandwagon so far. I found and read this article, which explains Wikia affiliations and gives examples of how to affiliate wikis. Basically, there is no "official" way to form an affiliation; rather, interested wikis just have to reach an agreement, keep in contact, and put a banner of some kind to show that each wiki is part of the affiliation.

Since the K-ON! Wiki seems to already be part of the anime/manga group, as clear by the banner at the bottom of the main page, I think we can take some ideas from that template.