Recently Google has updated their Webmaster Guidelines
page. You can get a little more detail from this article on the Webmaster Central Blog
by Vanessa Fox who heads up the Webmaster Central Team.
In a nutshell Webmaster Central Team have made a few things a little clearer than they were previously. No Major changes that I can see.
Anyone who is interested in the free traffic that Google provides also known as traffic through organic search, needs to keep up to date with their guidelines.