there were several confusing driver updates in oct/november! - including a rom update:

http://www.versiontracker.com/dyn/moreinfo/macosx/21573

http://www.versiontracker.com/dyn/moreinfo/macosx/14357

http://www.versiontracker.com/dyn/moreinfo/macosx/21572

the apple os also shipped with different drivers.