Apple yesterday seeded OS X Mountain Lion Golden Master to registered developers, concluding the a six-plus month long development process for the updated operating system. OS X Mountain Lion carries the version number 10.8, and succeeds OS X 10.7 Lion as Apple’s primary operating system installed on all new Apple desktops and laptops.

Historically, “Golden Master” builds given to developers are the same exact releases that are pushed to consumers for sale, usually merely weeks later – though there have been instances of the official release being a slightly, yet not significantly, different build.

Apple has provided developers with the following list of known issues:

Known Issues
⁃ Network Migration requires OS X 10.7.3 or later in this Developer Preview
⁃ International users may be unable to enter a Wi-Fi password while in Setup Assistant. Users can select Other Network Options and continue setting up their system without a Wi-Fi network
⁃ On systems with FileVault enabled, the login window may be displayed incorrectly
⁃ Rotating an external display may cause a panic on AMD Radeon-based machines
⁃ QuickTime screen recordings may produce corrupted videos or cause an exception when run on machines with NVDIA graphics
⁃ Installation of Final Cut Studio 3 may cause a hang unless Automatic Graphics Switching is disabled in Energy Saver Preferences

OS X Mountain Lion comes as a 4.0 GB digitally distributed installation package delivered via the Mac App Store. Apple has said that Mountain Lion will arrive to consumers as a $19.99 upgrade by the end of July.