User blog comment:BertH/Introducing WAM/@comment-4528041-20130504164143/@comment-452-20130506130525

Well, Babar Suhail, I don't think it really matters, because plenty of people use both.

But you don't have to take our word for it, here are thousands of examples:
 * Google search: "welcome to the wikia"
 * Google: "This wikia is"
 * Google: "This wikia"

Unless Wikia Staff actually want to press the point in order to prevent their trademark being genericised, I see no problem with people calling this "the community central wikia", or calling it "the world of warcraft wikia".

If Wikia, Inc. themselves don't care, then it doesn't really matter what is technically correct, since it's a common usage, and people know exactly what you mean when you say it. The point of language is to convey ideas, after all.