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I'd add optical drive in to that, too.

this is true, but you could prolly squish an optical drive down further than a harddrive, at least for now, in the furture sure anything is possible there just arent any on the horizon (harddrives that is that will fit smaller)
 
It's already thin if you compare to similar laptops in size. It won't get any thinner.

Plus Apple wants to tout the thinness of the Air for some time longer.
 
Also Ethernet… Firewire ports… Optical drives… Battery…

Apple can be very good at skimming off that last 1mm, but at the end of the day they have to work with what is available.

Besides, the perpetual quest to be thinner has some serious disadvantages.

Edit: I am slooow.
 
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