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.
target is new 
Interestng,
Regarding semantic search, I believe at the moment Microsoft is ahead of Google, since they integrated Powerset (http://en.wikipedia.org/wiki/Powerset_%28company%29), an US/Italian company that provides Bing’s innovative semantic engine. Even if still only available for US users, this technology is groundbreaking and potentially a win.
Unfortunately, nowadays small businesses can’t focus on SEO for 2 different SE like the 2 above, since they use totally different techniques of kw stemming and therefore totally different SEO rules are required (at least when building the content, maybe less on the linking and meta part). This problem will grow jointly with the success of Bing.
In my opinion businesses would achieve better ROI by pushing their presence in all those online properties that will score high rankings on SE (wikis, social networks, news…) while driving potentially huge amounts of traffic to who understands how to be relevant there. This is what Google defined Universal SEO and is now reality in almost each SERP provided by google and bing every day.
Agree! As we always preach it; create an exploding strategy. A smart and active social presence is far more effective than a SE-optimized website of your own…