I have been wondering in the past 2 years, why Google spend much effort to tell webmasters about how they rank web sites etc. For example, Google's
What Google is doing is creating a whole market of SEO gaming, resulting bad search results, lots of bad sites with lots of ads that are returned as top results in web search, and the perpetual tech escalation fight between search engines and quick money schemers. 〔☛ Spy vs Spy; Tech Geekers vs Spammers〕
Why doesn't Google shut up about how how their search engine works? After all, it's not something relevant to consumers or web site creators. If a site wants to be popular, there's the universal method, just like books, art, film: make it a good quality site.
Today, Google's Matt Cutts talks about it.
Google's point of view is that, by giving SEO advices, Google helps webmasters create quality websites. So, when more sites are quality, people enjoy the web more, and it also helps Google selling ads too.
A good perspective. Though, am not sure, that the overall effect of this approach is better.