Security groups are reporting an instant 66% drop in worldwide spam delivery yesterday. The drop was precipitated by the California-based servers of a single company, McColo Corp., being disconnected from the Internet following an investigative report by the Washington Post. The director of marketing for one of the two ISPs involved took a strong stance.

“We shut them down,” Ng said. “We looked into it a bit, saw the size and scope of the problem [washingtonpost.com was] reporting and said ‘Holy cow!’ Within the hour we had terminated all of our connections to them.”

Kudos to the Washington Post for its invesigation and the ISPs for acting so swiftly.