Have you noticed? Millennials appear to be everywhere. Not that this group -- the sizable cohort born between 1981 and 1997, now estimated at 75.4 million Americans -- was ever invisible. What’s changed is their status. Pampered and acclaimed, fussed over by recruiters, annunciated by the press, dissected by psychologists and analyzed by statisticians, the millennial generation has fully come into its own, and that means big changes to the design and implementation of the modern workplace.