The Mac App Store offers downloads of Apple OS X 10.8 Mountain Lion for $19.99. It's a $10 drop from last year's 10.7 Lion release and it will only be available as a digital download via the Mac App Store. This version of OS X touts "over 200 new features" including iCloud integration, Messages app, Notification Center, Facebook integration, AirPlay Mirroring, Game Center, and more.