From Whiteboard Friday - The Biggest SEO Mistakes SEOmoz Has Ever Made

http://www.seomoz.org/blog/whiteboard-friday-the-biggest-seo-mistakes-seomoz-has-ever-made

"3. Recommending People Use H1 Tags with Keywords

This mistake is a little bit more subtle. For years, SEOmoz recommended including keywords in the H1 of pages. After we started doing formal machine learning correlation tests we found out that this tactic didn't actually help very much at all (including the keywords in normal text in bigger fonts worked essentially the same). This was a shame because it meant we wasted time and energy convincing our clients to update their H1s."