I didn't say that epub was worthless --- it's a useful format, just one w/ marked limitations in the currently available viewing programs, and w/ other limitations which no viewing program will be able to resolve for the foreseeable future (there is no extant H&J algorithm which will preclude stacks, and research into page building at the chapter level or higher is still in its infancy --- list of recently published papers here:
http://groups.google.com/group/comp....9?dmode=source )
While the vast majority of books may be handled adequately by epub (if one is willing to accept typographic infelicities such as stacks) there are many books which can't be and if those books are to exist in versions readable as ebooks, the only format suitable for them at this time is .pdf
William