What is it about this book that has captured our imaginations for so long? Are there aspects of it that seem dated?
About a year ago, Glenn Beck asked a guest who has written a book about society, "Are we in 1984 or Brave New World?" The author replied that our society is definitely characteristic of some elements of Brave New World, Huxley's concern that technology has superceded humanity.
Certainly, the concerns about the subtle conditioning of certain media and the programming of people's thoughts through selected sound bytes, biased reporting, etc. parallel the New World's society. The interest in consumerism and ignoring of Nature, too, is a relevant concern, as well.
Finally, the efforts of the society of the New World to keep everyone "happy" raises the question of the push in contemporary times to keep everyone from being depressed with Prozac, Zoloft, and other related drugs. The "everybody belongs to everybody" is not too far from the casual sex of many young people, as well.
I suspect that there are a couple factors. It's an interesting story with some elements of science fiction, suggesting things like in vitro fertilization which was impossible at the time but which have happened since. The story predicts a future where promiscuity (by our definition) is acceptable and encouraged, where drugs are used to escape from the pressures of many realities, where pleasure is sought over meaning --- in short, a world in many ways reminiscent of our own. I think this is why the book is so popular. It was written a while ago (1932), and yet many of the things it seems to predict have become part of our everday lives ... and we wonder how much of the other things it predicts may come true. Huxley wrote an "addition" to the book: "Brave New World Revisited." Published in 1958, it contains additional information/theories that also seem to be coming to be today.
If you'd like to see something, go to youtube and search for Huxley and Mike Wallace. There are 3 short videos (about 9 minutes each) that contain an interview between the two in 1958. It's very interesting and also predictive of the future .... I provided a link to the transcript of the interview below.