Khronos Group's release of the OpenGL 4.0 specification moves the Mac platform further into the mainstream, as it moves more development onto standards that won't require a different code base on Macs than elsewhere. Moreover, the specification makes it easier for developers to leverage the various computational resources that appear in Apple products, improving performance for all applications on the platform by helping Apple hardware saturate computational resources with applications' demands, allowing Apple to offer even more price/performance to customers of anyone's software.
For example, close integration of OpenCL and OpenGL to allow coprocessors to handle more complex tasks without involvement of the CPU will both invite development under standards that make it easier for Apple to deliver a high-performance experience to users, and make it easier for developers to develop once a code base designed to leverage hardware acceleration enabled on any platform capable of delivering it, while giving every platform a reason to better optimize drivers for both OpenCL and OpenGL (since both will be expected to be in higher demand). The era of the proprietary graphics API and of non-portability to Macs receives another nail in its coffin with the new standards.
Already, standards-compliant resources like WebKit and OpenGL have moved Valve's software to more platform-independent development, so that Apple's platform gets new game title releases the same day as the major gaming consoles and competing operating systems – a circumstance that never would have happened a decade ago, regardless the performance of Apple's hardware. Moreover, because Apple's platforms will be running native code, not a ported quickie version or emulation, they will be able to deliver all the hardware acceleration Apple's environment can offer to code conforming to the standards.
Increased use of OpenCL, OpenGL, newer versions of HTML designed to support rich content, and so forth will all result in Apple's platform being able to deliver more predictably high-performance output. The move to standards favors Apple because it lowers the barrier to having applications run natively on Macs, and improves the quality of the software experience Apple can offer every customer of all its platforms.
Apple's strategy of embracing standards is a way to ensure it remains competitive as developers seek increasingly powerful ways to ensure their code remains valuable in the future.