I don’t know if you caught the news that a copy of the Google guidelines for website quality raters was leaked, but if you managed to grab a copy it was a meaty document weighing in at 125 pages.
If you persevered and read the whole thing you’ll have a good idea of what Google are looking for in a quality website. If you didn’t or couldn’t read it, there was a great summary of 16 insights posted by Dr Pete on SEOmoz.
Rather than write my own version or even just repeat what he says, you’ll do much better to hop on over to SEOmoz and read Pete’s article itself. He draws some very interesting conclusions from the document which will help you look at your site from Google’s perspective.
http://www.seomoz.org/blog/16-insights-into-googles-rating-guidelines
