A recent study conducted by Dr. Sam Vaknin of Google keywords over the past several years reveals that content created by teenagers and young adults on Wikipedia or social networks are often touted by the search engine as the most authoritative pages on a given subject.
The article also states that "This is Google's policy now: Wikipedia articles regardless of their
length or quality or even mere existence are placed by Google's
algorithm high up in the search results."
So son't you think there is some intimate relationship between Google and Wikipedia. However. it is said that googles latest algorithm codenamed Big Daddy, still calculates page ranks according to the number of incoming links.
The study also reveals that "the more incoming links from MySpace a Website has - the higher it is placed in the search results" . So webmasters now know what they have to look for.
You can read the article here