The INTJ and scientist in me just loves these kinds of cheesy "studies", so many holes in them just like Swiss cheese, I should read the actual peer journal article to see it is being correctly portrayed before calling it bullocks...but that is pretty much what it is based on the gazette summary. I love this part (it's a longish excerpt but give it a read).
"The researchers estimated that only 4.6 percent of a person’s happiness in a given moment was attributable to the specific activity he or she was doing, whereas a person’s mind-wandering status accounted for about 10.8 percent of his or her happiness.
Time-lag analyses conducted by the researchers suggested that their subjects’ mind-wandering was generally the cause, not the consequence, of their unhappiness.
“Many philosophical and religious traditions teach that happiness is to be found by living in the moment, and practitioners are trained to resist mind wandering and to ‘be here now,’†Killingsworth and Gilbert note in Science. “These traditions suggest that a wandering mind is an unhappy mind.â€
Let's start with the conclusion wandering mind = unhappy mind, yet not two paragraphs above it states mind-wandering accounts for twice as much of your happiness (10.8%) as your specific activity (4.6%). That is, your task is not making you happy nearly as much as your mind wandering is. This wasn't acceptable so the researchers just reinterpreted the data, I mean conducted a time lag analysis, after all it must have taken so long to press that button, their emotions were slow so to respond and the thoughts so complex people really couldn't properly attribute where their happiness lies. I guess the author figured your mind would wander before you got to their conclusion; you'd just forget the data. Wait where was I?
Oh yeah, the philosophical traditions, that's pretty vague as well, lets just go with the eastern meditative traditions...it's more these traditions teach the wanting mind is an unhappy mind. It is when the mind wanders into wanting and worry that it becomes "unhappy."