When Mojo tells the boys about the girls, Brick is on the right, Butch is in the center, and Boomer is on the left. When the boys say "Yeah!" in response to Mojo's words, Brick and Butch change positions.
When the Rowdyruff Boys throw the vehicles at the Powerpuff Girls, the shadows of the vehicles are shown approaching them in an overhead shot. After the girls take off, however, the shadows have disappeared.
When the Rowdyruff boys cover the girls in smoke, Blossom's mouth doesn't move when she coughs.