Love my 13" MBA. I don't mind the missing backlit feature that much; however, I'm not sure the direction they traded it for. Now, they do have a very nice sounding speaker system under that keyboard making some spacial sound that's way better than my previous mac laptops. However, for the purpose of the Air, that's the last machine I'd expect big audio sound from the built-in speakers.
For the purpose of it's use, (which is usually a little more silent (that is, personal and not for everybody to hear)), I'd think the backlit would've been a feature more in demand instead of the sound system they kind of replaced it with. You generally don't buy an ultra-portable for the purpose of great spacial sound for the room to hear. You usually stick with headphones. Just an observation about why they decided to put such effort into laptop speaker audio, on the thing. Still, it is impressive. My old Gateway laptop, with full visible stereo speakers doesn't even compete with the sound out of the 13" MBA, and that machine was *made* with the intention of making loud noises as a desktop replacement and Crysis-playing machine.