No the battery life just isn't long enough for tablets. If we ever get good quality color e-ink then yes, that might work.
Have you ever seen Jean-Luc Picard read or write on a piece of paper? Except of course antique pbooks.
What's funny is watching them gather up a whole stack of Padds, just like they were books. What's the point of having massive portable storage if you're just going to treat them like a stack of books anyway?