Now there is nothing new about rating the search results between Yahoo and Google. I have seen an incredible amount of tools, articles, and other websites do this in volume in order to draw some conclusions. In my experience I use Yahoo and Google both for different things, where Google is more for research and Yahoo is to find things Google can't seem to find.
Some of the forum members have taken it upon themselves in a collabrative light hearted effort to do a survey type experience between Yahoo and Google of the top 5 results. Quite similar to how Barry created with RustySearch, except its just a rating based on if you think the result is relevant to the search, you give the site one point, if not its gets 0 points. You add the points together and it decides the most relevant search query for either engine. Now nothing can be drawn conclusively from this as the sample size is limited and subjective. But the main interest are the phrases they are using in this little survey and the amount of people that have participated. It should be noted that most of the keyphrases I see being used are in ultra competitive areas like "asbestos lawyer" "ringtones" which can be assumed are schewed in some fashion. Its almost but not quite an assesment on the quality that SEO brings to the top 5 and how each of the engines react. If you are guessing Yahoo is suffering in this area, then you guess right, as the results in the thread are leaning towards less relevancy at Yahoo. But thats just opinions. :-)
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