As of yesterday, April 11th at 12pm West Coast US time, Google officially announced the release of the Google Panda / Farmer update in all English speaking countries. The official post can be found here on the Official Google Webmaster Central blog.
People are already reporting ranking drops and gains (although it's very early days to make any real conclusions), it seems sites that have put the effort in to make their content unique and useful are gaining.
If you haven't already, this certainly seems like a good time to review your site's content. Check out our guide to avoid the Panda update on eCommerce sites.
Additionally seek out poor performing content by finding high bounce rate pages in your analytics package. Either try to improve the quality of this content or consider removing it altogether. Watch those aggressive Adsense placements too!
Image credit zidane_0120
Post by Further search marketing.