Apple just released Mac Wi-Fi Update 1.0. The 1.49MB update, recommended for all late 2012 Mac systems, according to the folks in Cupertino, improves the compatibility when using the 5GHz band Wi-Fi. Like always, you speed-hungry Wi-Fi users can download the update directly from Apple or via Software Update. More info:
This update is recommended for all late 2012 Mac systems. This 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
/System/Library/Extensions/IO80211Family.kext/Contents/PlugIns/AirPortBrcm4331.kext/Contents/Info.plist
[Apple]