They've rolled out the update globally to all English-language Google users. "We will continue testing and refining the change before expanding to additional languages, and we’ll be sure to post an update when we have more to share," says Google's Amit Singhal.
Singhal also says Google has incorporated "new user feedback signals".
"In some high-confidence situations, we are beginning to incorporate data about the sites that users block into our algorithms," he says. "In addition, this change also goes deeper into the 'long tail' of low-quality websites to return higher-quality results where the algorithm might not have been able to make an assessment before. The impact of these new signals is smaller in scope than the original change: about 2% of U.S. queries are affected by a reasonable amount, compared with almost 12% of U.S. queries for the original change."
It would be very interesting to know what constitutes a "high-confidence situation". Domain blocking as a ranking signal could be a tricky area, in terms of the potential for abuse. The company has said in the past that it would look at making this a ranking signal, and that it would tread lightly.
"Based on our testing, we've found the algorithm is very accurate at detecting site quality," he says. "If you believe your site is high-quality and has been impacted by this change, we encourage you to evaluate the different aspects of your site extensively."
Well, that's exactly what we've seen a lot of sites doing. Whether or not it has been working for them remains to be seen. It's going to be a matter of time.
Singhal does say webmasters should look at Google's own quality guidelines. He also suggests posting in the Webmaster Help Forum. "While we aren’t making any manual exceptions, we will consider this feedback as we continue to refine our algorithms," he says.
Now the fun really begins. Now we can see how hard some of the sites that were already heavily impacted by the Panda update get hit on a global scale.