This animation uses the "Tween" effect to move the balls. The "Transform" tool was used to rotate the "8" in the middle of the 8-ball. The balls don't actually rotate, as the lighting highlights would look wrong.
A white rectangular matte is also tweened along with the 8-ball. Underneath that matte is the text. GIF Animator 5's use of object-based animation makes this job fairly easy.
Original concept for this belongs to an MSN Groups member known as "Largs®."