Thanks for the US-CERT/FBI links, we'll report to them. We've reported the site through Google's safe browsing form and the registrar and host abuse addresses. Both registrar and host replied saying they found no malware on the site, despite us submitting analysis on it.
I don't think ICANN deals with malware, but we'll contact the registry. We've also considered DMCA, but we think it would be a very temporary solution.