Today's big reveal at WWDC in San Francisco was definitely the unveiling of the Retina Display MacBook Pro. However, Apple also talked about OS X Mountain Lion, the next iteration of OS X.
Apple today confirmed that Mountain Lion will be arriving at the Mac App Store next month and will be priced at $20. The OS update will include the Messages app; Notification Center; system-wide sharing, which will allow you to share photos, videos and other files over third party services at the click of a button without switching apps; Dictation; Power Nap, which keeps your computer up to date while sleeping with auto refreshes of Mail, Contacts, Calendar, Reminders, and Documents in the cloud; AirPlay Mirroring; Game Center; and Gatekeeper, a security setting that allows you to set your computer so that it will only accept software downloaded from the Mac App Store, or from the Mac App Store and identified developers.
"The pace of innovation on the Mac is amazing, OS X Mountain Lion comes just a year after the incredibly successful launch of Lion," said Philip Schiller, Apple’s senior vice president of Worldwide Marketing. "With iCloud built right in and the new Notification Center, Messages, Dictation, Facebook integration and more, this is the best OS X yet."
Apple is also promising built-in support for Facebook in a later update to OS X Mountain Lion. This will allow you to post photos, links, and comments with locations right from your apps. Facebook notifications will work with Notification Center and you'll also be able to update your status right from Notification Center.