You've got: an advisory from the U.S. government. The newly ordained Department of Homeland Security (DHS) has asked its National Cyber Security Division (NCSD) to roll out the National Cyber Alert System. The system is intended to provide timely and actionable information to Americans with the explicit purpose of assisting the public in securing their computers and minimizing emerging threats.
Threats are aggregated, analyzed, and graded by the United States Computer Emergency Readiness Team (US-CERT), which is a cooperative effort between the government and the private sector intended to secure cyberspace. U.S. Citizens, or anyone else who joins the mailing list, can sign up to have e-mail alerts sent directly to their inboxes.
To meet NCSD's goal of "empowering citizens," information contained in US-CERT advisories ranges from technical to non-technical how-to's and best practices.

"The development and initial operating capability of the National Cyber Alert System elevates awareness and helps improve America's IT security posture," said Amit Yoran, director of the National Cyber Security Division. "We are focused on making the threats and recommended actions easier for all computer users to understand, prioritize, and act upon. We recognize the importance and urgency of our mission and are taking action."

The first alerts issued covered the MyDoom/Novarg.A virus and a new variant defined as MyDoom.B. The MyDoom spin-off targets Microsoft for a denial of service attack.

Aside from receiving details on the latest threats to hit the Internet, visitors to the US-CERT Web site can report incidents and vulnerabilities. Threats will not be color-coded at this time like those issued as part of the terrorism warning system