Ever changing algorithms and requirements making keeping up to date on the best methods to improve SEO ranking difficult. Fortunately, Searchmetrics has recently released their 2013 SEO ranking factor survey, and an accompanying infographic to demonstrate their findings this year.
Illustrated in the infographic below they take a look at the commonalities that all high ranking sites have. Interestingly enough this year they have found some new insight into the role social media plays in SEO. Pages with more +1's, shares, and likes had strong SEO rankings. +1's had the most impact, followed by Facebook shares. Backlinks still play a very strong role in page SEO as well. However, it was found that overall brands didn't have to have perfect optimization so long as they were also supported by strong social signals and backlinks.