http://blog.wolfire.com/2010/01/Why-you-should-use-OpenGL-an...
and a follow up:
http://blog.wolfire.com/2010/01/DirectX-vs-OpenGL-revisited
http://blog.wolfire.com/2010/01/Why-you-should-use-OpenGL-an...
and a follow up:
http://blog.wolfire.com/2010/01/DirectX-vs-OpenGL-revisited