The AppleCare staff received Mountain Lion via redeem codes over the weekend with the same build number, 12A269, as the Gold Master build launched by Apple to developers a fortnight ago.
AppleCare representatives have been trialling Mountain Lion on specific Macs for a couple of weeks, according to 9to5Mac, “but today’s news marks that the OS X Mountain Lion Golden Master seed has been supplied to representatives to be installed on their main work Macs.”
It is believed Apple will follow last year’s pattern and launch the new OS X after its quarterly financial announcement Wednesday morning, a theory backed by reports that Apple retail stores are ready to hold ‘overnight’ sessions to revamp the store’s computers with Mountain Lion.
Mountain Lion will bring Gatekeeper to the Mac App Store, a new security feature that is designed to protect Mac OS X users from malicious software, but it will not work with all Macs that currently run OS X Lion. To see if your computer will accept the upgrade, click here.