The demo unit at my place of labor (my university's bookstore's computer department) arrived (but only the demo unit, much to the disappointment of the 40 people that pre-ordered an MBA). Naturally, it's just a 1.6 with the HDD.
Of course, it's a clean machine, but it was still rather swift (for everyday tasks). Garageband took a decent amount of time to load (but it was still faster than my former 1.5 Core Solo Mac mini, of course).
It's so thin and sleek, I was absolutely mesmerized. The fit-and-finish for the port slide-out could use some examining, however; in the close position, it still protrudes slightly. It's heavier than you'd think it is, too. I thought it would be a featherweight, but it felt substantial, like the iPhone. I'd count that more as a benefit, however. In contrast with the Sony TZ, which feels like nothing, the Air has substance.
One of the full-timers wanted to try out remote disk, but either the installation screwed up or the school's network isn't remote disk-friendly since we couldn't get it to work (to be fair, the installation of the drivers was completed a minute before closing, giving us little time to experiment.
Given the way the MBA is designed (both the computer and the packaging), it's clear to me the direction Apple's going with the MBA. The iMac was revolutionary because in how it eliminated legacy ports and floppy drives, features that people bemoaned and have now become myth to the younger generation. Media is shifting towards online distribution as the younger generation, making the requirement of an internal optical drive less absolute. Many mobile devices use Bluetooth or Wi-Fi, either natively or through accessories, reducing amount of USB ports needed. Wi-Fi hotspots are also increasing and as 802.11 technology improves, wireless speeds and coverage will improve, making ethernet, and not Wi-Fi, the optional connection means. As airlines retrofit their planes and acquire new planes, power ports are being added; new airport terminals increasingly have easy-access power ports, and many public areas are making power ports more accessible. With access to electricity becoming easier and the power brick being shrunken, the integrated battery becomes less of a crippling factor. The only thing the MBA really needs in order to be as revolutionary as the iMac is an internal tri-band HSDPA/UTMS radio, as cellular internet is increasing in coverage and speeds, as well. Sure, IBM/Lenovo's X series has been around for a while, but Apple receives a lot more media coverage, is more prominent in the mainstream consciousness, and tends to be more influential in the technology industry than IBM/Lenovo.