A WebmasterWorld thread has discussion around a possible Google Panda update.

This would be version 3.9 and happening only a little over 2 weeks after the last update, Google Panda 3.8.

There are SEOs and webmasters claiming recoveries from previous Panda damage and other webmasters claiming major drops in their rankings. Because some webmasters who were hit by Panda are claiming recoveries, this seems to be a Panda related update and not a Penguin update.

To be honest, I am not sure if this is indeed a real update. There is a nice number of posts in the forums but not typical levels of a Panda or Penguin refresh.

I will reach out to Google for a comment and update this post when I hear back.

Past Panda Updates:

Panda 3.8 on June 25th
Panda 3.7 on June 9th
Panda 3.6 on April 27th
Panda 3.5 on April 19th
Panda 3.4 on March 23rd
Panda 3.3 on about February 26th
Panda 3.2 on about January 15thPanda 3.1 on November 18th
Panda 2.5.3 on October 19/20th
Panda 2.5.2 on October 13th
Panda 2.5.1 on October 9th
Panda 2.5 on September 28th
Panda 2.4 in August
Panda 2.3 on around July 22nd.
Panda 2.2 on June 18th or so.
Panda 2.1 on May 9th or so.
Panda 2.0 on April 11th or so.
Panda 1.0 on February 24th

Forum discussion at WebmasterWorld.

Update: Google said there was no specific update.