The same thing Apple does — physically driven interactions.
There are no time based animations, everything is driven by mouse position, so that user feels much more in control. For example, notice how axes appear, hover bubbles change color, and selected line strenghtens, as you move the mouse more into chart's frame (increase 'engagement with component').
This effect is subtle but important.
Try it on http://hover-data-concept.tomaskafka.com
Problems: How to do this on the iPad? Touchscreens don't have hover - the important 'non-biding expression of interest'. Clicks are binding (every time you click on the web, you lose the actual page and its state), so casual users are less likely to play with nice stuff - they got burned too many times for clicking in the past. So far this is desktop only thing...