I bought one
I could understand if the seller came by these Airs, and used current information on Apple's website to describe them. Old descriptions would no longer be available to copy and paste, and typing in all the descriptions wasn't seen as necessary. This strikes me as the most likely explanation for such a low price.
In the end, however, I bought one. The cautions expressed here made me hesitant, but I'm willing to believe that not everyone is unethical and that extends to the seller of these MacBook Airs. It's just as plausible that the seller lucked upon the assets of a business that went bust, preempting their distribution to its sales force. The lot size isn't an unreasonable amount that a small business could have purchased, only to see its funding rapidly dry up in this upside down economy.
In the context of Apple's other laptops, the entry level MacBook Air is a bit underpowered and costly. And, let's face it, this MacBook has to cost the least to manufacture when compared to the rest of Apple's portable offerings.
This deal *seems* too good to be true, but that wasn't enough to keep me away by itself.