http://www.theregister.co.uk/2010/03/06/microsoft_courier_details_report/
To me it looks like a lot better form factor, and like I described here somewhere a few weeks ago for an ebook reader.
I saw something about this on a techy show a LONG time ago. I'd completely forgotten about it! Well, it may have been this, or maybe not, but it definitely had dual screens with a book like action whilst reading it.
It has to be good for the consumer to get some serious competition going in the sector.