The specs apparently. Try looking at them again.
Bingo. Remember, this is a machine that is slimmer than the hump on a MBA13 (so ultimately, slimmer, though the body "lifts up" at the rear when the hinge is opened - a deliberate design, for obvious reasons), lighter, has a higher resolution display, also has a backlit KB, has a full speed dual core (no ULV), manages about the same real world battery life, has an included (in EUR, it's optional) dock with a HD6650m GPU, 1600x900 or 1920x1080 panel (both considered among the best quality TN panels to exist on a laptop... bar none). It also can use a slice battery option, which still makes this laptop very thin, but at least double the battery life.
Oh, and it packs, somehow, 2 SSD drives in there, stock (admittedly, of custom design), each with it's own link to the Intel controller (so can go RAID or just have two SSD drives, lol).
Yes, it's pricier than a MBA, but it blows it away in almost every HW aspect, and then some.
Perhaps, its only flaw is the lack of a DisplayPort output. People willing to plunk down 2000usd, min, for a laptop, are rather likely to have good displays... which excede the HDMI real world spec of 1920x1200@60Hz output. It's the one, and only, consideration for why I want a MBA13 (though I'm waiting on the rumored April Ivy Bridge release).