However, sometimes a Google algorithm change is substantial enough that even those who don’t spend a lot of time focusing on the algorithms notice it. That seems to be the case with what those discussing it at Webmaster World have named “Mayday”. Last week at Google I/O, I was on a panel with Googler Matt Cutts who said, when asked during Q&A,  ”this is an algorithmic change in Google, looking for higher quality sites to surface for long tail queries. It went through vigorous testing and isn’t going to be rolled back.”

"Google Confirms “Mayday” Update Impacts Long Tail Traffic"

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