I do really like this post... It shows - with its Q&A structure - how the so called quality factors are now taking their revenge over "automatic" ones. Yes, links and old SEO factors are still important, but the Google seems to be seriously looking to the user experience in how to rank a site instead of another.
The intention is surely correct, the steps toward that direction can be "wrong" is some of their details... but no big change is without errors.
I suggest you also to check the extended "linkography" given by Richard Baxter to dig even more into this subject.
Great, comprehensively written piece. Nice to see so much info on high authority site ranking factors in one place. Especially like the section on thinly written, or filler, content. I believe in the long term, users ability to share, rate and comment on content (did you find this useful?) can greatly separate the wheat from the chaff. I wonder also how the Google +1 button will effect this.