Much has been written about a study released by user interface guru, Jakob Nielsen, which says that reading on ebooks is generally slower than doing the same on paper.
Apart from the issue of the sample, which was quite small (only 24 book readers), Nielsen conveniently ignored the fact that people do not necessarily buy Ebooks (or printed matter) because of how fast they can read text on a screen.
Instead, Ebooks trounce paperbacks for convenience and the sheer reading volume that can be packed into such a small space. Electronic books also reintroduce serendipity in reading in that you don't have to plan ahead which books you will be bringing with you on a train or on a trip.
Just bring the equivalent of the Alexandria library in your backpack wherever you go and indeed, this is where electronic books score their most vital points. Just by allowing avid readers to take reading breaks when they want and where they want, this could potentially cause reading times to surge.
Also as some have put it, one reason why people read slower on an electronic media like the iPad is that people have yet to adapt to reading habits on such media but then reading was never a matter of speed (except during crunch tests or exams), instead, it was always supposed to be done leisurely.