In a time of material excess, time and attention are the most precious things left to us. While books may have originally been primarily useful for preserving knowledge over long periods of time (or to guard against a person with necessary knowledge being hit by a bus^H^H^Hbuffalo), in modern times, they're primarily useful so we don't need to consult storytellers and sages to transmit culture and knowledge. The time of experts and culture is precious - unless you're lucky enough to go to a reading by your favourite authors or happen to be at a university, chances are you're using books or other less-interactive media for these things. There's nothing necessarily wrong with this - books are a lesser way to move words around, but we have the advantages of scale, convenience, and repeatability. Digitising books doesn't help that much (except for annotation, an idea that we really haven't explored very well). The key factor is noninteractivity - even new media attempts at digital teaching (e.g. Khan Academy) are so far mostly finding new ways to book-ify more of the learning experience (they do extend the notion of what a book is).
Interactive time with an expert (or sage) will probably always be hard and expensive for most people. Finding ways to lessen the commitment of these people in providing it helps lessen that - they might not have time to teach a 12 week class at your university or to show up somewhere and answer random questions, but they might be able to get into the habit of relatively small-commitment gatherings - in the sciences it's even easier.
Chances are decent that many of you have read about this from another source, but for those who missed it, Ask a Biologist is a submit-a-question site for biology, and a number of academes will pick up whatever questions they're interested and post responses. It's kind of like Yahoo Answers, but with mostly experts, without the arbitrary closing of questions after a certain time, and with a heavy academic bent. As Marcus Aurelius said, 「The opinion of 10,000 men is of no value if none of them know anything about the subject」. So far, I've had a good time reading the site - it started in Britain (as the domain name will tell you) and gets a lot of schoolkids, but I get the feeling I'm not the only older geek on the site. So far I've asked two questions about Mitochondria (a topic I find rather interesting) and one on Gametogenesis - two of the three responses were good, the other was a bit off because I didn't state my question clearly enough.