Continuity mistake: Diana spins herself into Wonder Woman before she enters the gym. Watch the trash can behind her - it suddenly disappears. Additionally, in the widescreen version, a security guard can be seen standing between the car and metal door, though surely Diana would not transform into Wonder Woman in right front of someone (the guard is not visible in the original fullscreen version). (00:35:45)
Continuity mistake: When Mariposa is skydiving out of the plane, any time he's seen from afar, he's wearing a black oxygen mask. When the camera is closer to Mariposa, he's not wearing a mask. However, when he lands, he is wearing a mask.
Visible crew/equipment: After Wonder Woman rescues Nadia's boyfriend by tossing the two bad guys off screen, you can see the shadow of a stage hand adjusting a prop of some kind. This can be seen directly behind Wonder Woman as she's grabbing the rope to go and tie the two bad guys together.
Answer: The transformation twirling was invented for the 1970s TV series only, to explain her quick change from Diana Prince to Wonder Woman. However, it would have been nice to do a little spin homage in the movie.