A nice aside in Steven Johnson’s recent review of the new Kindle:
6. No page numbers! They have “location” numbers instead, because pages don’t really exist in the Kindle, given that you can resize the type with two quick taps on the keyboard. There’s a small question here about how you cite a passage from a Kindle e-book, but I think it begs a larger, and more interesting question about standardizing page references in all e-books — including Google Books for instance. (I’m going to write a longer piece on this…)
This isn’t really a new problem – anyone who has used a text from Project Gutenberg has run into this issue (try citing a passage from Heart of Darkness, for example). However, the difficulty may become more prevalent as devices such as the Kindle become more common. Of course, electronic books also present difficulties when it comes to marginalia (the most notable marginalia is probably that of Fermat).
There are some general difficulties here with electronic text and it will be interesting to see how they can be solved in effective, portable ways.