This week has been a mess for Google's search results, despite Google denying anything is going on to me.
There were some tools that sparked up on November 14th that I didn't see from the webmaster chatter.
This whole week, I've been seeing a lot of sporadic complaints in both WebmasterWorld and Google Webmaster Help forums. Typically, these sporadic reports, at least I think, mean Google targeted a link network and some sites were majorly impacted by it. It also may be a weird Google bug. But not necessarily a Google update. Of course, it could be that Panda was updated, which Google stopped confirming.
It is hard to tell.
The tools are all lighting up over the past few days. Moz has warmer than normal temperature the past couple days, SERPs.com has higher volatility numbers than normal, SERP Metrics shows higher flux than normal and Algoroo is in the red the past couple days. Something seems to be up.
Is it a major algorithm update - I don't think so. If I had to guess, maybe Panda was rerun or maybe Google squashed some sort of link network.
I am honestly not sure but Google is indeed a bit rocky the past few days.
Forum discussion at WebmasterWorld and Google Webmaster Help.