Google silently released Panda 2.5 this week, and the smell has polluted the web.  This latest revision of Google’s much-maligned machine learning algorithm has identified and punished such evil spammers as Technorati, GamerPro, and MotorTrend.

According to SearchMetrics, Technorati lost 73% of it’s search engine visibility in Google, GamePro lost 65%, and MotorTrend lost 31%.  Obviously these sites are not spammers.  Google’s little machine is seriously broken and no one inside the GooglePlex seems serious about fixing it.

Panda 1.0 rolled out in February with serious bugs, notably decimating quality web sites such as The British Medical Journal, Merck Manuals, AskTheBuilder, and the Math Forum at Drexel University.  Most notable about Panda 1.0 is that it actually benefited eHow.com — which most people considerd the most important anti-spam target on the web.

Panda 2.0 rolled out in April and finally hit eHow, but it also managed to decimate a huge number of quality web sites, including RegHardware, Computing.net, ComputerWeekly, TechRadar, TechWatch, TechEye, PCAdvisor, TechWorld, IT Pro Portal, Electric Pig, Pocket Lint, PC World Business, and this one.

Panda 2.5 didn’t hurt everyone, of course.  Search is a zero-sum game.  Whenever there are loser, there are winners.  The big winners from Panda include YouTube.com and Android.com — both owned by Google. No one has yet figured out how to work around the Panda algorithm, but being owned by Google appears to be one important factor in doing well in the new search results.

Tonight we drink a toast to our fallen comrades at Technorati, GamerPro, and MotorTrend.  We express sympathy for their losses and wish them speedy recoveries.  We also express sympathy for the larger group of losers in these Panda updates — the hundreds of millions of people who use Google to search the web and are now suffering from far lower quality in their search results.

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