I would like to see a more open system for all devices, hopefully with only one format. Lacking that, I wonder if it would be possible to get hard numbers and statics as to what is selling best (where and how). I know kindle does well - so does B&N nook. Kobo is

not sure and Sony? No matter how much I've been

over the 950 - I have no real idea as to the quality of the store or the experience.
A lot of people here speak of the difficulties of using dedicated devices with tech and text books. As a fantasy reader I often miss flipping back to study maps and the cast of characters/dictionary. I'm starting to wonder if there is a difference in major functionality and/or use between the formats and if certain formats work better for certain uses or types of books.
Not sure if I'm explaining myself well -