Windows has just released their patch for the WMF exploit early. Their goal was to have the patch ready for the January 10th update cycle, but it seems they have finished their testing and are ready to release early.
Sadly, it seems there will be no update for Windows 98 or later systems. However, Steve Gibson has been heard in the GRC newsgroups saying that if Microsoft didn’t release a patch for Win9x, he would gladly write his own patch.
Link to the security bulletin: http://www.microsoft.com/technet/security/Bulletin/MS06-001.mspx