Price point is too high for the average person who just wants to send e-mail, listen to music, etc. They'll go for cheaper over thinner - that's my bet anyway.
Edit: Added, people who want to import/watch/listen to DVDs/CDs will be baffled by the silliness of remote disc. Also good luck getting remote disc to work if Leopard on your MBA decides to stop working.
It's strange. You and others think that because people are doing "lighter applications" (like word processing, email, internet, listening to media) that they are going to want to pay less for a computer than if they were using the computer for video or 3d rendering.
That doesn't make sense at all. For many people, the value of the machine is NOT to run higher-end apps, because they have no use for such software. The value of the machine is that it's VERY LIGHT and VERY SMALL, which is something that higher-powered computers definitely are not. It's like you're taking your own value system (which does not value size and weight above hardware performance), and you're applying it to other people that you don't understand.
Imagine that you're a professional writer who's on-the-go a lot. Are you really going to stop yourself from getting a $1799 Mac that will lighten your load BY HALF (which is very important to you), when no other Mac in that price range can do that? Just think: are you going to insist on paying $1200 or $1800 on a Macbook or Macbook Pro, which has features you never use, but weighs too much? Or are you going to choose the machine that suits your work habits and needs more closely?
For many people, the Macbook Air is going to suit their needs better than a Macbook or Macbook Pro. When a machine suits people's needs, they're willing to pay for it, as long as its price is reasonable. And compared to other 3 pound computers, the Macbook Air's price is reasonable...
Really, I think the problem with this thread is that it's populated by too many teenagers and college students that who have a skewed sense of value...