SEOs love to complain about Wikipedia's rankings in Google. It seems that no matter what you're searching for, there'll be a Wikipedia listing. Michael Gray noted this to be true with popular actors and single character searches. Russ Jones checked out rankings for 600 keywords and found that 96% of them returned a Wikipedia page. And Loren Baker shows us how Google traffic to Wikipedia has been growing at an incredible pace (a good indicator of high rankings).
Well today I felt the need to add some additional in depth analysis to this on-going debate. In a matter of minutes I discovered that Wikipedia ranks #3 for anything, #5 for everything, and #3 for nothing. Interestingly enough, this data is contradicted by additional research which revealed that Wikipedia doesn't rank for all things or even many things. It also just barely makes the first results page for some things.
So what does this all mean? I don't know, but my head is spinning 
- Does PageRank Matter?
- Tracking Universal Results and Rankings Revisted
- SEO. No, not that one.
- A Blank Page Ranks #3
- Bundling Content to Target Keywords
Entries (RSS)
You're tempting fate with that additional research
I bet the Wikipedia SEO dominance will be much different a year from now because they will either become a Google company or a Google will penalize them because they won't become a Google company. Or the social aspect of their nofollow policy will start hurting. Or Facebook will take over and now Microsoft just bought in. Wow, it feels like the The Rocky Horror Picture Show just came over me!
It is surprising that Wikipedia hasn't been purchased by anyone. It seems to be in line with Yahoo's content push and would fit in nicely with the less formal Answers product.
Wikipedia could also hurt itself should it's plans for a search engine ever take off. Such a service would get Google's attention.