In regards to the extra battery - I would've thought the whole point of having a spare was so that if the cybook died while you were busy reading, you could easily whip off the cover, replace the battery and continue reading (after all, you can't read while it's charging [what a stupid idea THAT is!].
Well, replacing the battery is easy...providing you always carry around a miniture flat headed screw driver and some way of getting hold of that tiny little wire so you can actually unplug the depleted battery!
I'm in the middle of a really good bit in my book and I can't go any further cos I can't unplug the depleted battery and I can't read while charging
Ok, rant over - I'm going to go and watch paint dry