Yesterday, we reported that there was some suspicion from webmasters that Google had tweaked the Panda Update yet again on October 20.
Barry Schwartz at Search Engine Roundtable, who pointed to some of this discussion in the WebmasterWorld forums dubbed it Panda 2.5.3.
We reached out to Google for confirmation that what these webmasters were experiencing was indeed a tweak to Panda. As you may know, Google makes hundreds of algorithm changes a year, and it's always possible that various changes can impact your search visibility.
Google finally got back to us, saying that there was no Panda update on October 20 or on October 19.
It would not have been much of a surprise if there had been a Panda tweak on that date, as Google's head of web spam, Matt Cutts, recently said that we should expect more tweaks over the coming weeks.
I would expect that we will continue to see additional Panda Updates, and possibly even more tweaks to the most recent major version, but it doesn't look like that's what it was this time.
It does illustrate the lesson that there are so many different ways your content's visibility can fluctuate in Google's search results. Panda has certainly been a controversial example, and it's fun to talk about because of its name and all, but there are unnamed changes happening constantly, and any one of them could potentially affect your site.