NewScientist.com asked computer scientist Richard McCreadie of the University of Glasgow, UK, to determine if
Google’s Panda update and Microsoft Bing’s efforts are winning this war. The answer…. they are.

Here’s some quotes from the article.

As recently as March, for example, the first 10 results from a Google search for “how to organise your desktop” contained nine links to pages churned out by “content farms” – websites that publish reams of articles, often of dubious quality, that aim simply to attract clicks and advertising dollars.

The results are striking. In the case of the marathon query, sites that contained lists of generic tips, such as “invest in a good pair of running shoes”, were present in the top 10 in March but had disappeared by August, while high-quality sources, such as Runner’s World magazine, now appear near the top. Similar trends were found throughout the 50 queries.

Check out the whole article here