I have to say it, how could you be so unfaithfull to your K3?????
Sorry for that , but in all honesty i have also contemplated getting another brand that will accept different formats so i really don't see why you can't enjoy both.
What is the coloured viewing experience like??? i only ever viewed it on a MiGear reader and it was truly awful so it wasn't a fair unit to use for comparison, i will be interested to hear your opinion after a month or so, so enjoy your Nook, but just give K3 a little pat ocassionally ..