Looks like we had a Google algorithm update over the weekend, starting probably late Friday, October 6th and rolling out over the weekend. Most took notice on Saturday October 7th but the chatter is still fairly strong and will likely remain strong for the net couple of days.
The ongoing WebmasterWorld thread has a lot of weekend chatter around Google ranking shuffles and changes. Here are some of those comments from the thread:

I am seeing our site appear number 1 then number 2 then number 3 or 4 in incognito. Google is now shuffling the serps!

I am seeing now some massive changes on search the Friday 13th update may have been brought forward…. if I’m right I brag naming rights as the “Sunday B|oody Sunday Update” happy!

Huge improvments on my side. +65% comparing this sunday with last sunday.

Looks like my organic traffic is now back to normal and I’m seeing slight increase.

I don’t think we should name it the Sunday Bloody Sunday Update – since the update started before Sunday. Maybe you can call it the Columbus Weekend update since today is Columbus Day or something Fred related or we can not name it anything.
Here are the tools, almost all of them showing significant changes in Google:
Mozcast:
Algoroo:
SEMRush:
Accuranker:
SERP Metrics:
Advanced Web Rankings:
RankRanger:
RankRanger is the only tool not showing changes, which is weird – maybe there is a bug with their software or maybe they see something no one else does?
In any event, I don’t see any comments from Google on this and I am honestly tired of asking Google about these updates. Maybe that will change with Danny Sullivan joining Google or maybe it won’t? We will see.
Did you notice changes? Let us know.
Forum discussion at WebmasterWorld.

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