H-Security has published an article (http://www.h-online.com/security/news/item/Large-scale-attack-on-WordPress-996628.html) discussing a new series of attacks against WordPress-based sites.
Multiple ISPs have been hit including GoDaddy, Bluehost, Dreamhost, Network Solutions and Media Temple. There is one report that even sites built with the most current version of WordPress have been compromised.
We will update as we have more information, at this point I recommend reading the H-Security article for the summary of the scripts being added and contacting your hosting provider if you have concerns about your site. (c) SANS Internet Storm Center. http://isc.sans.org Creative Commons Attribution-Noncommercial 3.0 United States License.