But what if I don't need an optical drive? I use my MacBook Air for taking notes, surfing the web, getting work done, etc.
The only time I've needed to borrow my iMacs optical drive was to do a clean install when I got it.
Why do I need more than 80 gb? Or more than 2 gb ram? Or a firewire port? Or an ethernet port when I EXCLUSIVELY use my wireless network?
For what it's meant to do, the air is fine. Compared to the MacBook, yes it is underpowered (though the rev 2 Air is a closer match than my rev 1...) - but you're paying for the design. Compared to the white plastic macbook, the air is a completely different animal. I will admit that with the newer MacBook being a lot lighter, it will make the decision harder for some people.
But all I wanted was a super portable machine with a good sized screen and keyboard and the air satisfies that demand. I end up taking the computer everywhere because of its weight and dimensions and am very productive with it. The screen is gorgeous, too, and far better than the MacBook screen (why don't they use the same screen? perhaps to cut costs?).