Wisdom of the Crowd for Search Rankings - Business Week

The founder of Wikipedia plans to take on the giant by offering search results that tap the knowledge of people across the Web

The new search engine will rely on the support of a volunteer community of users. The idea is that Web surfers and programmers will be able to bring their collective intelligence to bear, to fine-tune search results and make the experience more effective for everyone. "If you search in Google, a lot of the results are very, very good and a lot of the results are very, very bad," says Wales. What that shows, Wales says, is that mathematical formulas alone do not produce consistently relevant results. "Human intelligence is still a very important part of the process," he says.
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When a user performs a search on Wikiasari, the engine will return results based on a formula akin to Google's own Page-Rank system, which determines relevance by counting the number of times other Web pages link to a specific page, among other things. Unlike Google, however, users will then be able to reorder the results based on which links they find most useful by selecting an edit function.

The article doesn’t mention how they will prevent gaming the system. Wikipedia doesn’t give a financial incentive to manipulate pages – this will.