The API is here for every Mac owner to use. And the SDK is included in every install DVD of the OS.
Here's what this all means in layman's terms: Apple isn't allowing Flash to become more efficient on their Mac OS X/Safari platform (or their iPod/iPhone/iPad one, either) by not providing the access to the hardware it needs to reduce its CPU load. Adobe is waiting and watching to see if they do, but, as Ozer says "the ball is in Apple's court."