I recently received my Kindle PW after a really long wait (Friend from the US brought it over to Europe) ... and sent it back.
For reading in bright conditions, my Kindle Keyboard does the better job - the Paperwhite looked "washed out" when using the light, and very similar when not using the light.
For nighttime reading, my old (1st generation) Kindle Fire was much brighter, much sharper and I like the user interface more (being used to it, that is). I know that there are people who consider the "darkest" setting on the Kindle Fire still too bright - for those, the PW might make sense. When I had them side-by-side, the light level was comparable when the PW was at a "middle" setting and the Fire at its lowest setting. Similarly, the "brightest" setting on the PW was corresponding to a "middle" setting on the Fire. The darkest setting of the PW ("suggested for reading in dark rooms") was way too dark for nighttime reading without a lamp, IMO. I had a hard time to make out the text.
So, given my very special case - having both the Kindle Keyboard AND the Kindle Fire - yes, the Paperwhite might have worked as replacement, but it would have been a compromise, and it would not have been as good as either of the other two at their respective specialties. But I wanted the *best*, and an actual improvement over the other two (which I understood the PW to be, from the advertisements on the amazon page). So back it went.
Last edited by Andy_T; 10-29-2012 at 12:40 PM.