November 07, 2012, 10:47 AM — In an average year, Google makes about 500 changes to its search engine algorithms. If it seems like Google has been making more-and bigger-algorithm adjustments lately, you're not just imaging things.
"Google is making big changes, and they're doing it faster than they used to," says Pete Meyers, president of User Effect, a website usability consulting firm, and a data scientist with SEOMoz. Meyers closely monitors and reports on Google algorithm updates for SEOMoz's Google Algorithm Change History.
Google owns about 66% of the search engine market share, according to comScore's September 2012 rankings, and this number has remained steady for several years. Even so, Google is getting "more competitive pressure" from Microsoft Bing and is therefore even more focused on improving its search engine technology, Meyers explains.
In addition, Google's revenue model is "maturing," he says. "They are getting to the point where revenues are plateauing. That puts additional pressure on improving their search results."
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The result: Since February 2011, with its widely reported Panda (also known as Farmer) update, Google has made some whopping algorithm updates. Here's what you need to know to make sure your SEO efforts are still paying off.
Google Panda: Putting Content Farms Out to Pasture
What it is: In February 2011, Google rolled out a major new algorithm. It was called "Farmer" because it was targeted at demoting high-volume content farms in Google search results. The update eventually became known as Panda, a reference to the name of Google engineer Navneet Panda. Since February 2011, Google Panda has been updated 20 times, Meyers says.
The initial Panda update reportedly affected the rankings of nearly 12% of all search results, according to the Search Engine Land blog.