Victor1 - 3:10 pm on Jun 14, 2010 (gmt 0)
Google's index is switching to a more story based approach. The search results are reflecting the 'story" regarding the keyword that google thinks is happening regarding the users. This is the direction of their algorithm I believe. Hence we see all the tinkering.
They didn't have strong or fast enough DCs in 2003 but now they do and that reflects the significance of Caffeine. Caffeine is measuring the "story" and based on that Google wants to give users the search results.
That is why over optamized sites are taking a hit. The keyword structure is not part of the "new story code algorithm" that they are using.
Seo is moving toward more Keywords in related silos where the keyword we are trying to rank for also fits in that root silo. So now one needs to see which Root Silos the keyword is in and use that as part of the SEO with less emphasis on the keyword you are trying to rank for. This is my observation of the changes and where I see it has gone and is going to go further.
Sites or writers that have done this naturally are not taking a hit. Yet it will take time for Google to sort this all out.