Some have speculated for years that Google has some secret crush Wikipedia. The human-edited “encyclopedia” ranks well for just about any search term for which it has an entry. Since Wikipedia is so massively interlinked, a lot of folks say that the “good” Wikipedia pages pass along PageRank to the cruddy pages… and thus they all rank well.

On Friday, Bill Tancer of Hitwise made an interesting point on the company’s blog: Wikipedia is extremely dependent on Google for it’s traffic. When Tancer graphed Google’s traffic to Wikipedia, and compared it to a graph of the encyclopedia’s overall traffic, the two were almost identical.

On the same token, Wikipedia makes up a big portion of Google’s “content”. Only Mountain View’s own Image Search and social networking powerhouse MySpace get more clicks in Google.

Now that Wikia, the company behind Wikipedia, has decided to take on the search engine industry, will things change? Google has made changes to the way it handles certain domains in the past (granted… none as big as Wikipedia - that I know of). Will Wikipedia suffer the same fate?

Flickr is one of the Internet’s largest collections of images. But the Yahoo!-owned company doesn’t really appear in Google Image Search. An image search for “apple” in Google and Yahoo! (which does index Flickr) illustrates the differences. Windows Live Spaces, a Microsoft property, shows up in Google. But when was the last time you saw a Live Spaces site rank well for anything (which could simply be because there aren’t many valuable pages there).

So it’s not unheard of for competitor’s content to show up in Google. But if Wikia really starts to compete with Google, will Wikipedia get the bump? It would affect both parties quite a bit. If Wikipedia begins to drive people to Wikia’s search engine, would it be worth the loss for Google?

I don’t know. I’m just throwing the idea out there. What do you think?