Google Content Farm update, that is going to be live from Thrusday in United States. Many webmaster has been effected by this update. Google prefer quality sites with quality content without any copying from anywhere.Again the content is fresh and relevant for user. Recently google is trying to fetch all the content farmers website manually but due to few changes and other feedback from webmaster ,google will update from their algorithms only.
Few of the sites that has been recently effected by Farmer's update More news here on Google Farmers Update