kaled - 3:25 pm on Oct 12, 2010 (gmt 0)
But, no matter how you cut it, you are comparing facts with guesswork, and no matter how clever the code is that is doing the guessing, it won't be as accurate as having the information handed over on a silver platter.
You are right, there is a potential for breach of privacy by use of referrer data from regular websites, however, simply because this might exist (or does exist) it does not let search engines off the hook. No matter how you look at it, by using POST, they could improve privacy of users. Personally, I think the case is marginal, but it should not be dismissed out of hand.