I don't think it has to do anything with Panda. I am waiting for members who are exposed to some big players' traffic stats to weigh in and share their observations.
At the first sight, it looks like a usual pre-holidays shopping season shake-up that favors e-commerce sites over content sites. Just may be a bit more aggressive than in the previous years. Few observations support this hypothesis
- I see large content sites in commercial niches down. I have a large content site which has been a leader in the niche (tech niche, but has many consumer electronics retailers) for years. It has never been hit by any penalty, including all Pandas, yet it is down 20% overnight and overranked for many keywords by Radioshack and alike
- Out of the 4-5 e-commerce sites that I have and that are leaders in their niche, the only one which has been affected is the one that has adsense blocks, i.e sells advertising in addition to having a shopping cart. Now that's interesting, lol. Coincidence?
- The exact match domains sites in commercial niches are all down (a long due), replaced by large retailers. I am not sure if it was a penalty to EMD sites, or a boost to large retailers. Most probably, the latter.
- Ebay is everywhere (gosh, was fed up with this junk before, now it looks even worse), walmart is up, all these huge e-commerce brands buying links on mega scale are up
So far about the holidays SERPs. Members with content sites who think it's another Panda wave, please look around, were you pushed down by e-commerce sites? any new ebay junk ranking above you?
Yet I also see some changes within non-commercial niches. I am not sure, but these look like some more "authority" boost, which still can be a side effect of pushing the mega retailers up the SERPs.