Could it simply be that they've made a fairly robust device, and offered little new in the recent models, so they are getting fewer upgrades (or purchases to replace faulty Kindles) and the sales are mainly new users?
I certainly have seen nothing that would make me reach into my pocket and upgrade/replace my DXG. Put out a new 9-10" e-ink device with the pearl screen & updated motherboard & software and I'll certainly consider it.
Are you listening Amazon?
