For all late 2012 Mac systems.
The Mac Wi-Fi Update improves compatibility when using the 5GHz band in Wi-Fi
Boot ROM or SMC Version Information: To confirm the update has been applied, the CFBundleVersion string of the AirPortBrcm4311.kext will need to be checked
New driver delivered in update: AirPortBrcm4331.kext CFBundleVersion = 612.20.15
Updated on Dec 18 2012