I switched to the Kindle Paperwhite from a Nook Simple Touch with Glowlight and these are the features I most like:
- Light allows me to read in any lighting situation
- Higher screen resolution
- Capacitive touch screen (it's more responsive, no accidental page turns, and those waterproof bags are now an option)
- Time to read feature (I like to end on new chapters, now I know how long this will take me)
- Being able to e-mail or "send to Kindle" and receive documents over Wifi instead of having to hook up to the computer every time
- Being able to delete documents from the device without hooking up to a computer
- Looking up words simpler (just press and hold), and the dictionary feature is leaps and bounds above the Nook's
- Highlighting is easier
- Automatic text justification means less time spent editing and converting files in Calibre
- Collections
- Being able to get suduko and a couple small games on there
- Cover that automatically puts you back to where you left off (okay, so that's extra but the NSTWGL didn't have it)
Things I kind of miss from the Nook are custom screensavers (but this isn't really an issue with the cover I have) and the way the Nook handled PDF files (flowing the text out so you could change the font size and read instead of having to always pan/zoom). I'm also still not used to having no physical buttons, and having to touch all the way over on the left margin to go back a page, but I will adapt.
Basically, if I could just get a Paperwhite that has a single-color screen (instead of technicolor shadows), I'd be vastly happy with the device.