Today Google rolled out panda globally to all English-language Google users, and also incorporated new user feedback signals into search results.
Google says, "In some high-confidence situations, we are beginning to incorporate data about the sites that users block into our algorithms. 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," stated Google.
"Based on our testing, we've found the algorithm is very accurate at detecting site quality. 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. Google's quality guidelines provide helpful information about how to improve your site.
As sites change, our algorithmic rankings will update to reflect that. In addition, you're welcome to post in our Webmaster Help Forums. While we aren't making any manual exceptions, we will consider this feedback as we continue to refine our algorithms," stated Google.
[Source: Webmaster Centeral Blog]