Apple has seeded the a new build of the OS X Mavericks Golden Master to developers, a little more than two weeks after the first GM seed. According to 9to5Mac, the build is only available for users performing a fresh install of Mavericks, with some users having luck re-installing the new GM over the prior version. The prior GM had a build number of 13A598, while the new release is build 13A603. Apple is reportedly targeting a late October launch for Mavericks and it's possible the company will give a final release date at
