JohnWayne

The Difficulty isn't in the port. A good DirectX programmer can switch to OpenGL without much trouble. The difficulty comes in the fact that you now have two rendering methods to maintain & different methods for handling shaders. It really multiplies even more work for the developer. There isn't really an economical reason to do so. Macs can now BootCamp Windows, or there's always Wine. DirectX has surpassed OPENGL when it comes to game related programming, it's only really used in Modeling/Animation programs these days.