There are high chances that another Google update might have happened on March 25th, 2014. Although no confirmation has been given by Google so far but there are speculations that a soft Panda update is in progress (Not sure, just my assumption). Matt Cutts had hinted earlier this month that a softer Panda update is coming.
Here are some links to the discussions currently happening around the web:
http://www.seroundtable.com/google-update-march-18313.html
http://www.webmasterworld.com/google/4650302.htm
Also See:
Google Updates Page Rank in Dec 2013
List of Google Updates
Panda Affected Sites and How to Fix the Issue?
Seo After Panda and Penguin Update
Infographic on Google Panda Update
Google Disavow Links Tool
Google Algorithm Change History
Google Panda Update 21
