The 2015 Diamondbacks are collectively throwing the ball harder than at any time since reliable data started being recorded.
We do not yet appear to have seen the first "official" 100 mph offering thrown by a Diamondback, as recorded by pitch f/X, but we have come close. While there have been park radar-guns which have reported three digits, the highest documented speed reached by an Arizona pitcher in the major-leagues this year is the 99.1 mph reached by Daniel Hudson on September 1, in the opening game of the double-header at Coors Field [Enrique Burgos, in case you were wondering, has topped out at 98.