Hardcore porn for SEO nuts

SEOmoz | Google vs. Bing: Correlation Analysis of Ranking Elements
http://www.seomoz.org/blog/google-vs-bing-correlation-analysis-of-ranking-elements

Search Engine Optimisation is a dark art. It's exemplified by the Google
Bomb.

As the article explains the most significant element of the Google system is being linked to by other well ranked sites. This algorithm is relatively simple. The clever bit is getting it to run in a fraction of a second. This is achieved by the true power of Google: the distributed computing system created by its founders. Google runs on lots of desktop computers with lots of RAM and no hard drive. These provide the number crunching power to run the ranking algorithm.

The article also explains some of the finesse of SEO. The old values of keywords are still relevant but being linked to from well ranked sites is still king.

Anyone who's spoken to an SEO consultant knows that this article is like Playboy's best edition. It's empirical for a start. The dark art is also dabbled in by consultants who don't use empirical evidence.