In 2009 Grzegorz Czajkowski from Google's system infrastructure team has published an article which didn't get much attention in the SEO community at the time. It was titled "Large-scale graph computing at Google" and gave an excellent insight into the future of Google's search. This article highlights some of the little known facts which lead to transformation of Google's algorithm in the last two years.
Cite
@article{arxiv.1201.2261,
title = {Relationships in Large-Scale Graph Computing},
author = {Dan Petrovic},
journal= {arXiv preprint arXiv:1201.2261},
year = {2015}
}