Sometime during Tuesday afternoon a third party Nissan LEAF forum, mynissanleaf.com got placed on a blacklist for malicious websites. Both Firefox and Google Chrome are advising against visiting the website. Visiting the website using Internet Explorer is NOT blocked, however after arriving at the site Windows asks for permission to install software, lending credence to the possibility that the LEAF forum has been infected with malware. Whatever you do do not install software from this website until the owners have had time to deal with the issue.
Update 2013-01-16: The website was cleared of malware later the same day. Apparently it was a victim of the Java cross-site vulnerability. Update your Java to the latest version.