Waterstone’s are planning to launch an ereader in spring 2012 but no specifications yet. Link for the same:
http://www.bbc.co.uk/news/technology-14841692
Apparently the new owners want Waterstone's to move in a new direction. I am not sure if they are also planning to introduce their own reading app or will license it from someone. Anyway we will get the details sooner or later.
din