The new build, which comes a week after Apple's last seed, included release notes describing the new features found in 10.8.2 like phone number support for iMessage and tighter integration with the forthcoming iOS 6.
Power Nap, the energy-saving feature that enables Macs to stay up to date by syncing with iCloud and automatically backing up data while the computer is in sleep mode, is now extended to support late-2010 MacBook Airs. Previously, compatibility was limited to mid-2011 or later MacBook Airs and the 15-inch MacBook Pro with Retina display.
Built-in Facebook functionality has also been bolstered to support single sign-ins, merging contact information with OS X Contacts and Notification Center compatibility. The features join system-wide sharing through Mountain Lion's Share Sheets.
As for iOS integration, incoming iMessages and FaceTime calls sent to an iPhone user's phone number will now be displayed in their respective OS X apps.