Just found this:
Press release: Danish Complaint Case may have Global Consequences for Apple. Essentially it says that under danish law, people can return their Apple iBooks for a refund, even after one year of use and past the warranty period, because they suffer from a design fault.
This looks similar to the Iliad -- the short battery time is a design fault. I also suspect that all the darkening screens are such.
Can we draw conclusions? Do we have disgruntled danish users here who could try to return it?