The headline is "Get Out Of Your Seat Or Die", which points to a rather less dramatic EurekAlert story, "Study links more time spent sitting to higher risk of death."
They found that more leisure time spent sitting was associated with higher risk of mortality, particularly in women. Women who reported more than six hours per day of sitting were 37 percent more likely to die during the time period studied than those who sat fewer than 3 hours a day. Men who sat more than 6 hours a day were 18 percent more likely to die than those who sat fewer than 3 hours per day. The association remained virtually unchanged after adjusting for physical activity level.
I don't see that this is all that dire, I'm actually astounded at how little difference it makes to sit around all day. 18 percent more is a pretty minor increase in what starts out as a very small number. So yay!
Of course there may be confounds in the other direction -- maybe office workers have some hidden advantages...