Wayne, a hacker, recently acquired a MacBook Air for repair, and surprisingly, this MacBook Air is a prototype. The MacRumors thread provides some information, though it should be taken with a grain of salt.
The processor in this « 2011 » model is said to be a 1.5 GHz Core i3 (Apple has always used Core i5/i7 in its MacBook Airs) with Intel HD 3000, specifically a Core i3-2377M. The keyboard is not a backlit model, even though the lighting seems to be present in the photos. Interestingly, the machine features USB 3.0 and a chipset from the 7 series (Ivy Bridge).
Mac OS X
Power Mac G3