The rumored "Google-killer" Wikia Search will be available in alpha form soon, according to an email to the Wikia Search
The service hopes to allow folks to contribute to how pages are ranked and will also allow folks to edit search results, ala Mahalo. The search project has apparently integrated the Grub search project, which was acquired by Wikia back in July of 2006. Grub uses user-donated distributed computing power to index the Web.
Jimmy Wales is best known for being the co-founder of Wikipedia, and has the high hopes of displacing other search companies with the new engine, although he's been careful not to explicitly call out Google.
Still, I imagine it will be easy from the initial view of the system to see if this is going to have the kind of traction required to be a major player in the search market, or if it is destined to be a supplementary useful utility like Wikipedia and Mahalo (or if it will be designated for the deeply undesirable third tier: useless).
We'll all be waiting with baited breath.