CFPreferences keys for OpenGL

Mac OS X's OpenGL framework (only Leopard tested) reads a bunch of values from defaults at app startup. They are:

Integer values

ColorBufferSizeKey
DepthBufferSizeKey
MultisampleKey
RendererIDKey
ThreadedEngineKey
AcceleratedMethodKey
MaxSwapsInFlightKey

Boolean values

ColorBufferSizeEnableKey
DepthBufferSizeEnableKey
VBLSyncEnableKey
MultisampleEnableKey
RendererIDEnableKey
AllowOfflineKey

I haven't been able to make these do anything... anyone know how to use them?