Decius - 9:31 am on May 2, 2011 (gmt 0)
Problem with that is it's a vote for or against a certain site. This information can be gamed.
Hell you could hire people use proxy servers and kill cookies to do it 400 times a day from different IPs.
Unless they restrict it to users who have Google accounts, and are logged in at that exact moment, which moves the feedback rate to a low single digits.
Even logging which result people click on promotes "catchy" titles and meta descriptions which is not indicative, in any way, of whether they found what they are looking for.
The only statistic I see, which is about 90% of what is of interest, is whether a person clicks on a link, goes to that site, and does not perform that search again within the next minute or so.
Which I suppose they could track with cookies... but doesn't that cause privacy issues? Are they allowed to store searches by IP or computer?