I noticed to of the sites I work on got a drop in the traffic. One lost 2/3 of the traffic and the other lost half of it traffic both happened over the weekend of this Oct, 25 with a slight dip in friday traffic the 23rd. It a little too new for the blogs to have mentioned it. Both sites are old, one is a legal website/blog in spanish that has hundreds of pages linked has linked google plus authorship but had pengiun problems in the past. Another one a old through up microsite that not been updated for years.
I know penguin rolled out on OCT 17 a full week in advance and there was no loss of traffic until a week later. I thinking if this could an aftershock.