I've actually had the H2O *seem* like it is still processing - just copying over a single book, it sat with the status bar at 6% (or some other number, that's just what it showed last night when this happened) for a long time, long past when it should have completed. The first time, when I went to do a hard shutdown via the power button, it immediately switched to sleep and then off. When I started it back up, everything seemed fine.
Next time this happened (its happened a handful of times, probably), I just hit the upper right corner of the screen as if to to open up the settings menu, and the screen screen refreshed just fine, light turned on, and off I went, no problems at all. Not sure what is preventing the screen from refreshing, but it has happened to me on two devices (annoyingly, I had an H2O completely crap out on me about a month back), so it seems firmware related. Hardly the end of the world, once you know
