Google’s new SearchWiki allows searchers to promote or eliminate pages from their own personal search results. You have to be logged into Google to personalize your results.
This new feature is an example of how search is becoming increasingly dynamic, giving people tools that make search even more useful to them in their daily lives.
While there is some debate about the usefulness of the tool and a small (so far) uproar over privacy concerns, Google continues to move forward in providing searches with better search results.
Search engine optimization will become more difficult as you will be optimizing across behavioral patterns instead of towards a single search engine. The top SEOs are already aware of how personalized search will affect optimizers and are prepared for the future.
You have to forget about rankings and focus in on return on investment (ROI).