Naturally, any eBook reader that people will enjoy using over time must be durable in order to last years--not just days or weeks.
With the price of flash storage dropping year after year, it's reasonable to expect that a GB of flash will cost under a dollar before long. And, it would seem that 50GB would be adequate (5GB would be the minimum). It's not the text that would be challenging but, instead, the multimedia such as audio, photos and videos.
8. Easy annotation
The basic form of annotation is the yellow highlighter that we've all used to highlight in textbooks while in school. Additional annotation is the writing we do in the margins and anywhere we want to over the text. This brings up a very big challenge: how to provide the right texture and feel that is like pen on paper but actually better? You would need to be able to select width and color of the line and, perhaps eventually, some electronic painting functions like filling a shape--but that's likely to be a higher end feature.
9. Easy access to the dictionary and synonyms/antonyms
Again, this eBook reader capability would make reading an eBook "better" than a regular book today, because you can't look up that interesting word in a paper-bound book. You want to be able to highlight a word and easily see the definition--most likely by simply tapping and holding the pen on top of the word.
10. Acceptable cost of device
I'm leaning more toward the cellular telephone and cable TV business model, where users pay a monthly fee and get the device (a set top box or phone) for little or no cost, as long as they sign up for a multiyear contract. Family plans will make this even more affordable. And schools may subscribe to educational eBooks and simply pay a monthly fee for each student.
While an educational computer may need a keyboard for composition writing, a consumer eBook reader certainly doesn't. We're talking something like $10 to $20 per month for a basic system and a lower number of books, and then perhaps something like $40 per month for a high-end system and access to more content.