On Tuesday, I posted the latest version of the Google Search Quality Rating Guidelines after an anonymous reader sent it to us.
This version is labelled version 3.18 and dated March 30, 2011. Since before this document, the earliest version I had was from back in April of 2007.
You can download the 2+ MB PDF file, which is 125 pages filled with Google insider nuggets by clicking here (It has been removed) but you can read the summary of the document at PotPieGirl. . The PDF is from Pot Pie Girl's blog post.
Most of the document goes through how these Google quality raters should use the quality scoring system. But it also spends a tremendous amount of time explaining how to classify pages and images and documents. This information can be very useful for SEOs in understanding what Google thinks quality versus non quality pages are, spam vs non spam and so on.
Forum discussion at Google +.
Note: This story was written earlier this week and scheduled to be published today.