Just maybe 10.9.3 begins to set the stage for Apple to introduce 4K monitors. Having Mac Pro doing 4K @60 is not enough. Apple needs Retina MacBooks doing 4K@60 as well.
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Apple Seeds OS X Mavericks 10.9.3 Build 13D43 to Developers
Tuesday April 15, 2014 4:22 pm PDT by Juli Clover
mavericks.pngApple today seeded build 13D43 of OS X 10.9.3 to developers, just under a week after releasing the sixth OS X beta, build 13D38, and a little over a month after the first 10.9.3 beta.
The beta is available through the Software Update mechanism in the Mac App Store as well as through the Mac Dev Center.
Apple continues to ask developers to focus on Graphics Drivers, Audio, Mail, Contacts and Calendar sync over USB in iTunes, and Safari. As was discovered with the first beta, 10.9.3 adds new support for 4K displays, offering "Retina" resolutions that improve readability along with support for 60Hz output from the Retina MacBook Pro.