<story><title>Google Recently Made A Silent Shift To A New Search Algorithm, “Hummingbird”</title><url>http://techcrunch.com/2013/09/26/google-recently-made-a-silent-shift-to-a-new-search-algorithm-hummingbird/</url></story><parent_chain><item><author>obilgic</author><text>I operate 2 websites that are exact clones of each others, the only difference is the domain. This algorithm change literally shifted %70 of the traffic from one of them to the other one, in a matter of hours.&lt;p&gt;Edit:&lt;p&gt;&lt;pre&gt;&lt;code&gt;    * Links to the websites, I would say almost identical
    * Same number of the pages are indexed by google, around ~5 million
    * Domains are almost same, no keyword difference
    * They both have same pagerank
    * Domains are registered together
    * Sites are hosted on different ips
    * Total traffic sites get is around ~40k&amp;#x2F;day unique
    * By this change, total unique increased by %10&lt;/code&gt;&lt;/pre&gt;</text></item></parent_chain><comment><author>rossjudson</author><text>Sounds like the algorithm noticed the duplication, and picked a &amp;quot;winner&amp;quot;. The new winner isn&amp;#x27;t the same as the old one.</text></comment>
<story><title>Google Recently Made A Silent Shift To A New Search Algorithm, “Hummingbird”</title><url>http://techcrunch.com/2013/09/26/google-recently-made-a-silent-shift-to-a-new-search-algorithm-hummingbird/</url></story><parent_chain><item><author>obilgic</author><text>I operate 2 websites that are exact clones of each others, the only difference is the domain. This algorithm change literally shifted %70 of the traffic from one of them to the other one, in a matter of hours.&lt;p&gt;Edit:&lt;p&gt;&lt;pre&gt;&lt;code&gt;    * Links to the websites, I would say almost identical
    * Same number of the pages are indexed by google, around ~5 million
    * Domains are almost same, no keyword difference
    * They both have same pagerank
    * Domains are registered together
    * Sites are hosted on different ips
    * Total traffic sites get is around ~40k&amp;#x2F;day unique
    * By this change, total unique increased by %10&lt;/code&gt;&lt;/pre&gt;</text></item></parent_chain><comment><author>Kudos</author><text>I doubt the incoming links are also identical.</text></comment>