If Intel already supported Open CL with its Sandy Bridge CPUs, this API was in fact working via the CPU, and not through the graphical unit (not enough powerful). So, it was more a compatibility-driven decision than rather a graphical performance-driven support.
The new IGP associated with the Ivy Bridge is now able to provide hardware-based graphics acceleration. So, Intel is now releasing the associated SDK:
This is an important step, as Mac OS X is built on Open CL. It also provides next generation MacBook Pro 13" and MacBook Air some hardware-based graphics acceleration, even if it should not transform the overall Open CL rendering.