User blog comment:Trellar/A new way to promote your wiki/@comment-4528041-20120830061449/@comment-2118812-20120830194255

We noticed that, too, and found a small bug that was causing some wikis to appear more than others. It's fixed now. :)

But, Wikia does also have the ability to give some wikis a higher level of priority so they'll appear more often. No wikis are being given priority right now, but in the future you might see that happen and that will explain why they show more frequently.