05-Dec-08 update: Webware posted an article describing the Koobface virus coming from Facebook.
I just received an email from our corporate IT department, as they are temporarily blocking Facebook and MySpace due to a worm infected file.
The method of infection is:I'm not sure how real it is, but it serves as a good reminder to make sure updates are coming from known URLs.
There is a prompt to update your flash player when visiting one of these sites . This executes a worm that infects explorer.exe and other critical operating system files. To date there is no easy method to clean an infected system. The IT staff is working to clean the 20 odd systems that have been affected to date.