Interesting. They are going to post details about the contest today.
For those who don't know about CastleCops:
CastleCops is a volunteer security community focused on making the Internet a safer place. All services to the public are free, including malware and rootkit cleanup of infected computers, malware and phish investigations and terminations, and searchable database lists of malware and file hashes.
Education and collaborative information sharing are among CastleCops' highest priorities. They are achieved by training our volunteer staff in our anti-malware, phishing, and rootkit academies and through additional services, including CastleCops forums, news, reviews, and continuing education.
CastleCops consistently works with industry experts and law enforcement to reach our ultimate goal in securing a safe and smart computing experience for everyone online.