The Myrgard Times has been covering the Myth III/nimda issue fairly well and Drunkbob has noted some important information:

Two very important notes about this whole virus thing: First off, do not run the uninstaller, this is apparently how the virus is primarily activated. Secondly, the Myth III demo is also infected.

Also, Rohan wrote a post at MWA guiding users how to rid of the virus. This should be a fine solution, but there will likely need to be some action taken by Take2 or Mumbo Jumbo.