From Joe: Shortly after the turn of the century, we all were being sold a bill of goods about the coolness factor of multitasking: New gadgets, a new generation of workers, instant communication, all this was presented to as really slick. Article after article represented anybody who did not joyfully and skillfully multitask as being an old fogey — most probably a male old fogey. (For example, a USAToday story with its subtext.)
A lot of research has been done on multitasking since that time. The gist of this research is that we pay a steep price for constantly switching our attention when we are doing something important.