Read all about it...
http://www.theregister.co.uk/content/54/29555.html
this could be something good... this could be somthing bad...
if its bad prepare for another antitrust suit, plus the possibility of the ARB suing their ass of depending on what it is...
if its good then horray for MS...
I for one must remain indifferent on the subject though ever suspicios(since i doubt "longhorn" wil support GL at all, also it is my suspision that that is what prompted the move), despite my dispise for MS, since until the last meeting they have been willing contributers to the OpenGL ARB, and have done little to hinder it within the ARB itself that is, though outside as you know is a different story altogether...
enough with my banter...