How can that be? Quadros revolve around OpenGL and have a little bit of DirectX implementation, while GeForce cards are the opposite. And so, if WMP10 uses DirectX for all its renderings, then that means that the GeForce card will deliver a much better performance than the Quadro. Assuming of course that we are comparing the top quadro and the top geforce.
And the GeForce also has higher core clock speeds and higher memory clock speeds, and thus a higher bandwidth or fill rate.