There are two main players in the field of e-books: Sony and Amazon. Both are subject to huge amounts of marketing, but are they dyslexia friendly? Until I can get hold of one, it is not easy to say. In theory they could be good, since they are electronic format, and therefore should be available in the way that other versions are available to use ones own preferences. But then where is the discussion of the text-to-speech and changeable background colours.
For a comparison, see http://news.cnet.com/8301-10784_3-9820409-7.html
Personally, with Negroponte looking to launch a new $100 machine in 2009 looking remarkably like an e-book, I am left wondering if this independent e-book has a short life as the sub-notebook looks to find its place.