In the press release Amazon has been bragging about a proprietary waveform algorithm driving the screen. Might be simple marketting hype or there might be something else going on. On ocassion, big customers have been know to help finance their supplier's manufacturing facility. (A couple years back, MS paid for an LCD-panel facility Toshiba was building. The screens ended up on Zune.)
So, it is not impossible the Amazon might have a deal for the first 6 month's worth of Pearl screen. Unusual but not impossible.
Would be nice to hear it from a semi-reputable source, though.