My Kindle 4NTs look as good as any of the new pics I have seen. I went through a few to get good screens. I am quite sure the screen is exactly the same in the new one...E-Ink has not released a better Pearl screen. Maybe they got some better quality control and the variation isn't as noticeable...or maybe the OP got a great one in the screen lottery this time and his old one wasn't so good. And the Black bezel WILL trick the eye to some degree. Also comparing cut outs etc is not going to prove anything since there is such a variation in Pearl batches and individual screens.
Regarding the paperwhite it's not looking so great now that photos are showing up. It looks identical to the current models with the light off. I had really hoped it would have an actually "whiter" background. Typical marketing misdirection.