When Google sent out mass mobile usability warnings to webmasters in January, some speculated a new algorithm was on the horizon, specifically designed to tackle mobile-unfriendly sites.
So when SEOs noticed significant fluctuations in rankings on Wednesday, the natural assumption was that we were witnessing the dawn of this long-rumoured mobile UX algorithm.
However, Search Engine Land (SEL) spoke to Google and was told there was "no specific 'update' to announce".
Google did confirm it was "continuing to make tweaks" to its search results, "as usual", but according to research by SEL writer Barry Schwartz, these tweaks are not affecting mobile-specific sites uniquely.
So, it seems this is unrelated to Google's push for better mobile usability. And from Google's statement, it seems unlikely to be Panda or Penguin-related either.
However, in his original Search Engine Roundtable post, Schwartz did speculate that the fluctuations "might be Panda related".
Was this a major update in disguise, or simply routine amendments on Google's part?
It's hard to say at the moment. At the time of writing, Mozcast's Weather Widget reports strong fluctuations of 80° on Thursday, slightly down from Wednesday's sweltering 90°.
We'll keep you posted.
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