I just received my paperwhite today and I see many of the same issues that the "naysayers" see.
My initial review would be 3 stars, mainly because the pw somehow loses something in translation compared to the KT (K5 if you prefer). But I had the touch with the case light. The case light was horrid. Hated it. Worst reading light ever. So the PW is able to be read in many light scenarios that is the beautiful thing about it.
The comparison to the K4B with book light wasnt exactly fair. Slap a booklight to the PW and turn down the light and you should see a comparable ereader (not a better mind you). turn the light up a tad for a better experience.
So far my pw does ok in no light, and low light, and superbly in medium to high ambient light. I havent seen any colorish blobs (but do see some dark spots and havent looked very hard) The fonts dont look as crisp as I would like, but nonetheless I am going to keep it and hope for a resolution in the coming months.
I would post pictures, but I am scared you guys would sabotage my thinking of the pw so I couldnt read with it anymore