Search Engine Optimization : why did my google position drop ?
A lot of webmasters experience this at least once in their life : after pushing their page or site at the top of google results on some keywords, this factor suddenly breaks and results in a heavy loss of google position and amount of visitors.
Well don't worry you're not the only one. Have a look at the links below from webmasters going through the same problem :

http://www.rlrouse.com/drop-in-rankings.html
http://www.articlecity.com/articles/computers_and_internet/article_864.shtml
http://webxadmin.free.fr/article.php?i=164
this one is from google answers and analyses a particular query :
http://answers.google.com/answers/threadview?id=220437

From what you can read in these different analysis of such a brutal change in google's results, it seems that these are due to the different algorithms used by the search engine, giving favor to one or another optimization technique or website construction strategy, depending on how the engine evolves. Given that is evolves all the time, you can never be sure which strategy to adopt. The answer to that is diversify, do not focus on one particular optimization technique.

Above all, first thing to do is to read carefully google's recommandations on the subject : http://www.google.com/intl/en/webmasters/index.html
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