Google Experimental Search

Google has added an experimental feature where you can vote up or reject search results. Looks like it only works for your results for now, but how long can it be before they start factoring this kind of information into the algorithm. As a sidenote, this made me think about Google Web History. I've been saying for a while it's the feature that speaks best to a future plan for Google: Recording all your web behavior and making recommendations based on collaborative filtering (a la Amazon's "people who like this like that"). If you haven't tried it, it's quite fascinating (the interesting items tend to be amazingly accurate).