In this post by Robert Scoble, he coined some interesting thoughts ont the developments of SEO and SEM. I especially found the ideas on the evolution of search engines like Google and Bing to search results that are relevant by heart and not by design interesting. It is an evolution to a semantic web in another way than mostly is promoted.
Most of the time the idea of the semantic web is linked to a better understanding of the question, of a smart determination of the question. Do you look for a bank to collect money, or to sit on. In the example of Scoble the semantic part is found in the search results itself. What results do really fit, apart from any influencing designing elements. It may look like just another accent but it is a world of difference.
So this will mean that the current services for search will evolve to semantic systems. Fed by the conversational realtime search and cloud based sensors to the real relevance. Services like Twine will be obsolete. We won’t call them semantic by the way, they are just intuitive and authentic.
Is SEO therefor also obsolete. Not completely. It will stay for some time, and it will be more and more a hygienic factor. A basic requirement you cannot avoid. It is just like the development of usability. Usability is not the discriminator, the experience and persuasion aspects of an interface are. SEO will be part of the basic toolset. The real behavior makes the difference.