Niche yes, small... I'm not so sure. Because of the screen tech (Eink, SiPix), the battery capacity and weight can be substantially reduced on the ereaders. They weight a little less than half as much as the iPad, and that can make a pretty big difference in terms of holding it comfortably while reading. That's not taking into account the eye strain issue which seem to affect some readers (of which I am not one, I like reading on my n800). Remains to be seen how big the niche will be, but it'll be interesting.