There were three updates in all:
• Mac Wi-Fi Update 1.0, recommended for all late 2012 Macs. The update improves your Mac’s performance when using the 5GHz band to connect to Wi-Fi. Users must be running OS X 10.8.2 to install this update.
• MacBook Pro Retina EFI Update Version 1.1, recommended for all late 2012 models of the 13-inch MacBook Pro with Retina display. The update improves the unit’s sleep performance, enhances support for the Thunderbolt router, fixes an HDMI display issue, and also improves compatibility when using the 5GHz band in Wi-Fi. Users must be running OS X 10.8.1 or newer for this update.
• iMac EFI Update 2.0, recommended for this year’s late-generation iMacs. Like the other updates, this download will help the computer perform better in the 5GHz band of Wi-Fi. It also includes performance fixes relating to the computer’s sleep function and Thunderbolt use. Like the MacBook Pro update, this download requires that users run at least OS X 10.8.1.
All three updates are available for free on Apple’s downloads page, or via the Mac App Store.