A very interesting article from Information Week, based on info from PandaLabs researchers.
http://www.darkreading.com/security/antivirus/showArticle.jhtml?articleID=218700073&cid=nl_DR_DAILY_H
http://www.darkreading.com/security/antivirus/showArticle.jhtml?articleID=218700073&cid=nl_DR_DAILY_H