Just a quick note: Boot Camp 4.0 does not uninstall the Boot Camp 3.0 drivers. Potentially those can conflict. The only one that I found that made a difference is on the mid 2010 Mac Mini the Nvidia graphics driver gives a .1 point higher rating in Windows Experience index. update: I have reverted to the Boot Camp 3.0 - my Kensington Trackball started jerking and moving on its own. After the revert (a restore) I went into the BootCamp 4.0 CD and went to the drivers folder where I located the Nvidia drivers and upgraded only those.