Google is currently running a Panda update, I believe it started sometime late Sunday night or early Monday morning.

A WebmasterWorld thread spotted it early and had some members talking about it early yesterday morning. Google later yesterday posted a note about a Panda update in their 20 search quality changes post. Google said:

A senior member said yesterday:

Other webmasters at the forums also took notice but it seems like it is still rolling out. Google said, “a handful [of these updates] are actually rolling out today and tomorrow.”

This update is just a “data refresh,” like the Panda 3.2 update on January 15th. A data refresh means there were no changes to the Panda algorithm, it means they only ran the algorithm again. So some sites were hit hard and some sites were freed and seeing a boost in traffic. Of course, a data refresh can be serious for sites, if they are on either side of the coin.

Like our one year Panda anniversary poll said, 87% are still suffering from Panda. So I hope many of you benefited from it.

Past Panda Updates:

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, DigitalPoint Forums & Google Webmaster Help.