Are fitness-tracking wristbands a fad? Probably, but the quantified self movement (of which fitness-tracking wristbands are only one small part) is going to be here for a good long while. So get ready... this is just the beginning.
With wearable technology, data will become the new astrology. We will use it to divine our personal futures and deconstruct our present. It will alter the "human ideal" and change the meaning of what we think of as "success."