I know the the title is verbose. Coming from a science background, this title is short. What it boils down to is Apple's OpenCL. It's the ability to allow the Mac to offload certain non-graphic operations to the video processor in your Mac and allow them to help out the main processor, the CPU.
This feature is ready supported in many graphics processors (dedicated or integrated), the GPU, from AMD and Nvidia but not by Intel's current integrated graphics processor.
I think the Macbook Air is plenty fast for what it was designed to do. Personally, I think heavier lifting should be handled by the Macbook Pro line. Still, I'm never one to pass up on anything faster.
We can see up to 60% increase in speed from the Macbook Airs by this time next year.