Ocean10000 - 9:20 pm on Feb 5, 2010 (gmt 0)
If any of you noticed this isn't talking about DOS based OS's. It actually talking about Windows NT based OS's, which was a ground up rebuild with more security in mind.
The problems being patched (at least my understanding) are in how Microsoft maintain compatibility with some older applications, thus making themselves vulnerable to attack. This older applications had bugs in them, but instead of Microsoft making them release fixes, they built a compatibility layer to work around these bugs.