Aaron Wall recently posted about why many of the best SEO ideas aren't found on popular blogs. His main points are that many people share incorrect and outdated information and it's dangerous to share the best tips because it could negatively affect you. If you expose a secret, it will be addressed shortly thereafter. The best secrets are those that nobody speaks of.
Over at Sphinn, this sentiment is reiterated:
There are a lot of people republishing stuff from 3 to 8 years ago that is no longer quite true, or is in some cases now totally wrong.
It's true. SEO is constantly evolving and those who test often will be more successful. Those who are newer are generally more interested in sharing their findings as well.
Forum discussion continues at Sphinn.