An hour or so before I went offline for Passover, the Google Analytics blog announced a very significant change to how Google search will be passing along referral data. In the past, a search for flowers and a click on that search result to your site, would show the URL:
http://www.google.com/search?hl=en&q=flowers&btnG=Google+Search
Now, you will see the referral string (in some cases, right now in beta):
http://www.google.com/url?sa=t&source=web&ct=res&cd=7&url=http%3A%2F%2Fwww.example.com%2Fmypage.htm&ei=0SjdSa-1N5O8M_qW8dQN&rct=j&q=flowers&usg=AFQjCNHJXSUh7Vw7oubPaO3tZOzz-F-u_w&sig2=X8uCFh6IoPtnwmvGMULQfw
The new format is broken down as such:
http://www.google.com/url?sa=t &source=web &ct=res &cd=7 &url=http%3A%2F%2Fwww.example.com%2Fmypage.htm &ei=0SjdSa-1N5O8M_qW8dQN&rct=j &q=flowers &usg=AFQjCNHJXSUh7Vw7oubPaO3tZOzz-F-u_w &sig2=X8uCFh6IoPtnwmvGMULQfw
Google's Matt Cutts confirmed on a BlogStorm blog post that Google may be passing along Google ranking data, along with this information.
Brett Crosby, the man behind Google Analytics, summed it up:
The key difference between these two urls is that instead of "/search?" the URL contains a "/url?". If you run your own analyses, be sure that you do not depend on the "/search?" portion of the URL to determine if a visit started with an organic search click. Google Analytics does not depend on the "/search?" string in the referrer, so users of Google Analytics will not notice a difference in their reports, but other analytics packages may need to adapt to this change in our referrer string to maintain accurate reports.
The folks at WebmasterWorld suspect this change is more about Google eventually migrating to AJAX search results, amongst other things.
Forum discussion at WebmasterWorld and Sphinn.
