Just listened to Mark Stein from ESPN on this trade. He spoke of the Chemistry hit that OKC just took with this trade.
IMO, I think this will be OKC's Kendrick Perkins-BOS effect - all over again. Looking at OKC from the outside, the entire team seemed to have great chemistry, but Westbrook, Durant, Harden formed the core of that as I think their best three. Their saving grace is that the season hasn't started yet, so they'll have some time to adjust to the change.
OKC will feel this one for a bit. They will still crush the lesser teams out there, but OKC took a HUGE chemistry hit, here.