The goodexperience folks think Yahoo should modify their search results to get in line with their marketing promotions, but I disagree. I think search results should be based on more objective, quantitative measures and not a tool for marketing types.
The Yahoo search engine is valuable because it provides a service. We have a certain expectation of that service – that it aggregates links to web sites and intelligently lets us search through those links. If you mix what is commonly understood as content with what is commonly understood as advertising you deceive readers and end up creating one big advertisement, thereby diluting the value of the service and decreasing loyalty in the long term.