As we gain these tools (and skills) we'll make a class of highly visual books, ideal for training and education, which we can study, rewind, and study again. They will be books we can watch or TV we can read.
My son is trying to teach himself how to maintain and service his high-end mountain bike. Although he's found some friendly local mechanics, and some decent online sites, it's clear that he's starving for just this sort of high-density absorbable information.
We will find out that books never wanted to be telephone directories, or hardware catalogs, or gargantuan lists. These are jobs that websites are much superior at -- all that updating and searching -- tasks that paper is not suited for. What books have always wanted was to be annotated, marked up, underlined, dog-eared, summarized, cross-referenced, hyperlinked, shared, and talked-to.
The future is one of change, with structure:
Wikipedia is a stream of edits, as anyone who has tried to make a citation to it realizes. Books too are becoming flows, as precursors of the work are written online, earlier versions published, corrections made, updates added, revised versions approved. A book is networked in time as well as space.
Kelly has written a nice essay, short enough to be approachable but filled with lots to consider; it's worth a read.