At SMX Advanced, Matt Cutts, Google’s head of search spam, announced that the Panda algorithm is still being updated roughly every month but that update is rolled out slowly throughout the month. It is like a Google Dance, but in this case, a Panda Dance.
What happens is Google will run the update on a particular day, let’s say on the 4th of the month. Then Google will slowly push out that impact over 10 days or so through the month. Google will typically repeat this cycle over monthly.
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