My philosophy on SEO is simple. When I search for something on Google, I want to find the content that is the best and most relevant to my search term, not the content whose creator was able to buy up the most links.
Google uses links as votes to gauge the popularity of a page or website. Those links that grow organically from other webmasters commenting about our material are the links that hold to the purest sense of that system of votes. Those links that are purchased, exchanged or in any other way manipulated are doing nothing more than diluting the purity of the results.
If your content is awesome, it will be linked by those who stand in awe and I will then find it when I search at Google, Yahoo, or Bing.
If it’s not amazing and I’m finding it when I search, it’s only because you’ve poisoned the system.
I’m quite impressed with most of the Google updates because each time it seems that they’re working to help move the algorithm toward a means of fostering this purist ideal.
Those sites that are awesome and are building organic, one way links get promoted. Those sites that are secretly working to pollute the system will get demoted.