And the rumors about the PW4 using a Mobius (i.e., plastic) substrate were just that, rumors (probably based on the concurrent release of the Kobo Forma, which does feature a Mobius backplane).
As Harry said, if it were using anything more interesting than usual, you'd have heard about it from Amazon's marketing team
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Case in point: the flush screen. Everyone agrees on that one. Strange, that, eh?
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