Long swings:
Ken Griffey Jr.
Ryan Howard
Adam LaRoche
Does not mean they cannot hit the ball a long way, but will strike out a lot because of the swing.
One key mechanical piece that points out a long swing is a high back elbow and the hands far back from the body. The tendancy is to drop the top hand parallel to the plate, creating a long swing.
If you watch Chase Utley take his practice swings, his hands are not terribly far back and his top hand stays more vertical as it comes straight toward the ball, creating the bat whip. He very rarely swings around the ball, meaning letting the ball get between his hands and his body.