You and others are presenting a logical fallacy that the parts equal the whole. This is like saying a new Lexus should be cheap because certain parts of the Lexus are inexpensive. How much does the MBA's aluminum unibody cost? (including mining and refining the metal?) The keyboard? The built-in camera? The speakers? The batteries? Trackpad? The screen? Etc. Etc. And, of course, if Apple's PR is correct, they're making sure it's all green stuff (recyclable and non-polluting) which might cost a bit more. Add that all up. Maybe it's still cheap. So, next question, could you buy all those parts and construct the MBA yourself for that cheap price? Most people can't or don't want to bother. So we do pay for someone to make it for us. Let's toss in the labor...
We know that's cheap because no one will pay for living-wage American labor, so all computers are made in China. That keeps the cost down even for Apple. Toss in all the shipping and handling and/or paying those who work at the store. And Apple does have a right to make a profit, that's why it's in business after all. It's not altruism. Adding all that together...how overpriced is it really? That $149 128 SSD is one component of the whole. The whole is $1200 (with 128). That makes it, what? 1/8th of the total price of the computer? Yet the computer isn't just that SSD, is it?
Now I'm not saying it's a cheap computer. As others have noted, there are plenty of cheap netbooks with more storage. But from the look of them, they don't have many other fine things. I don't know how well they run, how hot they get, how long their batteries last, how nice their screen is, how good the sound, if they have a camera, how long they'll last and how good their resale value will be, etc. All that has to be factored in if we're going to argue that the 11" MBA is grossly overpriced.
IMHO, while I'm sure it's at the high end, I'm not so sure that it's as obscenely overpriced as many here are making it sound. Of course, we all decide on what we're willing to pay for what. If you don't think anything that size with that little memory, only five hours of battery, etc. is worth $1,200, that's fine. You should buy the computer that gives you what you want at the price you're willing to pay. But, I think you're not being fair in your assessment of price by pointing out the price of 1/8th of the entire computer.
The parts do not equal the whole.