I have spotted several reports about a new search engine being developed by Wikia. They apparently are planning to rely in part on volunteer human ranking.

While reading about it, I found a critique on Sashdot by the founder of another search engine called "Majestic-12".

Search_Wikia:
   http://search.wikia.com/wiki/Search_Wikia

Majestic-12:
   http://www.majestic12.co.uk

some reports:
http://arstechnica.com/news.ars/post/20061225-8492.html
http://slashdot.org/article.pl?sid=06/12/26/1329230

another report (warning: flash):
http://www.tech2.com/india/news/internet/wikia-search-engine-coming-soon/3428/0

critique:
http://slashdot.org/comments.pl?sid=213642&cid=17366542