Recently Google released a new search feature which is available to any user who has a Google account, Google Search Wiki. In short, this service allows the user to promote or demote sites, or add comments about any web site. Your results customized your future search results, and your input anonymously becomes part of the collective Google Search Wiki. Thus, as the user community rates sites (with or without comments), any user can pull up search results which now give results based upon user feedback. I am calling this Google 2.0, or the Collective Intelligence of Search.
If you're intrigued with the concept, you may wish to watch a short tutorial which I've created. This Northstar Nerd screencast reviews the basic features when using Google Search Wiki:
- Google 2.0 - Collective Intelligence a la Wiki (tutorial / screencast)