SEO is constantly evolving year after year as Google and other search engines have defined better ways to sort out sites. What seems to be happening is a gradual shift from the quantity to the quality of the content of a site but still staying grounded to the basics of SEO which are creating worthwhile content and the use of keywords. There are reports that say that the movement from quantity of texts to the quality of the content of a site has somehow "killed" SEO; what they don't realize is that by merely coming up with high quality content, sites are already using SEO techniques. Updating and improving site content is basically one of the important foundations of SEO.