I think I might end up getting a Hanlin v3. It's a little cheaper than the Cybook, supports folders and looks to be a little more gpl compliant (even if it's not fully).
Cuppa then need to make my mind up and just buy one
OpenInkPot sounds great and will be something I will keep my eye on in the future, but doesn't really have much bearing on the Cybook vs Hanlin decision as it's supposed to be supporting both.