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.