Continuity mistake: At the end, when Inara is closing the lid on the trash container there are three shots. From behind Inara, she has her gun in her lap (in her right hand) and is waving with her left, but from Saffron's point of view Inara has both hands in her lap, then Inara is back to waving again.
Continuity mistake: During the duel, after Atherton breaks Mal's sword, he puts the blade to Mal's chest with his arm straight and his wrist slightly bent. The angle changes, and Atherton is suddenly holding the sword with his elbow bent and a straight wrist, in a completely different manner. (00:37:30)
Continuity mistake: Just prior to the crazy Ivan, Kaylee tells Jayne to cut the hydraulics to the port engine, yet it is the port engine which rotates to perform the maneuver. Also, the cut scenes of the engine thrusting just prior to and after the crazy Ivan are reversed.
Chosen answer: One of the premises of the show is that the two major Earth societies that survived, and ultimately merged, were the Chinese and Americans. As a result the common language includes much Chinese. Clothing, signage, and building designs also have a heavy Chinese influence.