Preview at WWDC likely in June, followed by September launch.
Apple Enabled GPU Hardware Decoding of H.264 on New MacBooks, Pros and Airs?
This suggests that the version of Mac OS X on newly released MacBooks, MacBook Pros and MacBook Airs based on the new NVIDIA chipsets now offers GPU-accelerated H.264 video decoding for the first time. While Apple has previously included graphics cards (such as the NVIDIA 8600M GT) that have contained hardware support for H.264 decoding, the company has apparently not previously taken advantage of it.
Multiple readers have confirmed similar findings on their new MacBooks and MacBook Pros, though it appears it can be movie-specific, as one video showed little difference between the machines. We assume the new MacBook Air would share the same advantage as it is based on the same graphics chipset as the new MacBook, though we haven't heard from an Air owner yet.
These changes could be based on improvements planned for Snow Leopard. Apple had previously announced that "QuickTime X" would be a feature in Snow Leopard to offer optimized media playback:
Using media technology pioneered in OS X iPhone, Snow Leopard introduces QuickTime X, which optimizes support for modern audio and video formats resulting in extremely efficient media playback.Readers should be reminded that without official confirmation from Apple, we are only speculating as to the reason behind the CPU usage difference. If true, however, we would hope that Apple would incorporate support for older Macs that have the necessary hardware in a future software update.
Old MacBook Pro