I'm thrilled to announce that after months of hard work, SEOmoz's biennial Search Engine Ranking Factors is finally launching. Every two years, we survey 100 of the industry's top SEO minds. In 2009, 72 SEOs participated in the data gathering process, answering survey questions that consumed hours of time. The resulting document is an amazing aggregation of data about how search engines rank documents and, at least in my opinion, should be read by anyone serious about practicing search engine optimization.

The document contains five important sections:

• The Overview - offering the most high level view of the ranking elements
• Ranking Factors - the raw data, showing the importance and level of consensus for each factor; this year also includes a set of opinions on how geo-targeting across countries is perceived.
• Link Building - this year, we've also added a section asking our SEO participants which methods they find most effective for link acquisition. I think this data is tremendously valuable and interesting for anyone seeking to engage in link building campaigns.
• Additional SEO Data - we asked a few specific questions around SEO to gauge the opinions of the experts; lots of cool stuff in here, too
• Contributors - a list of those who participated in the survey and details about who they are and where you can find them on the web

My great thanks goes out to Timmy & Sam here at SEOmoz, who helped create this year's document and to all of the generous participants from across the SEO world. Practitioners in more than a dozen countries around the world, all of whom have extremely busy schedules, gave up their time to help those learning SEO get a better view of the subject - please join me in thanking them.

If you've got questions, feedback or want to bring up interesting topics, feel free to do so in the comments on this post.