Windows Vista May Degrade OpenGL

The implementation of OpenGL on Windows Vista turns up an interesting debate. To summarize this issue,

a] A wrapper will be used to get OpenGL to work along with Direct3d. So, performance of OpenGL apps could face a performance hit of up to 50%.

b] Microsoft implemented the proprietary Direct3d and so created this situation of incompatibility between the two.

c] By creating a proprietary system for gaming, vendors would find no reason to port to Open GL based platforms such as GNU/Linux..?

The debate