From all the tracking tools it looks like one of the biggest Google Updates since June 2012 (at least if you go by the MozCast Metrics). Despite lots of forum chatter, there is no real indication yet of what this update is targeting.
One comment on Seroundtable shows tracking statistics that indicate that ranking fluctuations were seen on both the 4th and 5th February, which looking at the chart they posted (see below) may show that Google was trying something which was subsequently reversed. Although it could just be that the update is rolling out over many days. Hard to tell.
Another comment on that website mentioned that websites impacted by the Google Panda Penalty on a previous occasion do not seem to be affected, whereas someone else chimed in that a couple of Penguin Hit websites appeared to have made a good recovery.
You can get a good scale of how severe the movements are with all the following trackers:
So What Do We Know?
This is where things get tricky, especially if the reports of a roll back on any SERPs Changes turn out to be true. With the changes being so massive, but not a single SEO being able to point to a key signal on websites they are tracking (i.e. websites hit by Panda or by Penguin), it may be that this update is attempting to do something new. Furthermore, with fluctuations still happening (it has been known for some updates to be rolled out over a ten day period or even longer), we may not get a clear picture until the dust settles.
Glenn Gabe, a Digital Marketing Consultant, had this to say about the possibility it was a Panda update:
There could be some type of update going on, but I'm not seeing websites impacted by Panda moving very much. Just my 2 cents. :) #seo
— Glenn Gabe (@glenngabe) February 5, 2015
Marie Haynes posted images of two Penguin websites that are seeing good gains:
Google subsequently released an update:
Thanks for checking in — as usual, we're continuing to make tweaks, but we don't have a specific "update" to announce.
So obviously they are not ready to release information on this update. Usually, when something major happens such as this they are quick to make some kind of announcement, but the lack of information seems to imply something new, or that they are still testing the changes and that they may not stick.
There are some reports that Wikipedia is no longer dominating the search results like it used to:
Yes, there's some re-alignment going on, and I'm not sure it's finished just yet. Several SERPs showing Wikipedia no longer the top, or near the top. Some may argue that's a good thing, but when it's a commercial website above it, it makes you think it's not yet settled.
Have you been affected?
If you are noticing significant falls or recoveries, please let us know. The signals around the web are very mixed right now, so we will keep you updated as a clearer picture develops.