Well you should. Now. Seems there’s another (yes another) here-to-fore undiscovered vulnerability, this time affecting OpenType fonts. You probably don’t use OpenType, but it doesn’t really matter. You need to make sure the PC/Server/WinMobileDevice is up to date.
See the full story here, from ZDNet.
Just to beat the dead horse: don’t let updates lapse. Regularly update Windows, Java, Reader, and Flash, at a minimum. A little bit of caution goes a long way to preventing problems in the future.