Google are trying to shore up our algorithms with the wisdom of the crowds.
Personalized and social search are quickly coming upon us.

Customized Search is one of Google’s first steps into the realm of social search. It is allowing web publishers of all skills to create their own search engine dedicated to their particular branch of knowledge and interests. The social part comes in when the web publisher allows others to contribute selections to their search engine, growing your search engine into an even more valuable resource over time.
Social search is all about giving the power to the users. Google is empowering users by enabling them to slice their massive search engine into thousands of sub-topics. The question is, “How will Google use this collective knowledge?”
This new product could give them a wealth of data on the linking structure and popularity of websites around the Web, giving them yet another competitive advantage over other search engines.
Google could also use this new data to find authority sites among different topics, which could be very valuable information for improving mainstream search results.
Would these kinds of changes affect the world of search engine optimization? To some degree, they would, but for the most part these changes would simply improve upon the relevancy of results.
For the smart webmaster, they should have no trouble adapting to this new age of search. Quality has always served well for search engine rankings and the future of search is even more dependent upon quality content and authoritative websites.

Google custom search allows you to quickly create your own search engine by choosing which websites and directories you want to include in your index.

You can include only those sites or give those particular sites a higher ranking while still including the larg