From my friends at Sesmame Communications:
To find out what high-ranking pages in Google have in common, Searchmetrics examined the 30 top search results for 10,000 keywords, analyzing 300,000 websites.
Backlinks are a huge factor in helping pages rank high in Google. The study found that “the ‘most natural link profile’ possible and ‘diversity’ are keywords here.”
In regards to social, the study found that though social signals aren’t necessarily a factor for high rankings, the top URLs showed more social signals.
When analyzing the importance of technology in high search rankings, the study found that site speed is a must.