Hear hear!
I've been devouring books lately on my Kobo ereader. As a non-native English speaker I find some authors more challenging than others as they seem to enjoy highly specific words I've never encountered. So the built-in dictionary has been highly valued.
Some unknown words I've added to my word-list just lately: desultorily, promontory, rambunctious, intrasigence, smart, realcitrant, gregarious, triptych, garrulous.
I'll probably read Lord of the Rings on it too, despite the experience being even more atmospheric on paper. I want to read the books in their original language, so I'll be prepared with my dependable digital dictionary.