yes it does, with ideal photographs you can resize the canvas without skewing the subject. but honestly this appears to be more of a flash mothion tween than a photoshop thing.
i think, from what i have read, the cs4, action does not allow a gradual motion effect. i could be wrong. i am not sure the extent of it yet. that said this seem a lot more like a flash thing animation.
i think it is simply the subject and background being two separate entities and being resized independently of each other with a motion tween which gives a unique look. if the subject gets bigger faster than the background it will appear as if the subject is moving towards the camera. it seems quite simple really.
i could be way off but who knows.