I was just looking at an iPad in the Apple store, seeing how my website worked on it. I was very impressed by the iPad. But I really don't understand a particular engineering decision regarding how the mouse events are being mapped to finger/touch events in Safari.

SCENARIO: iPad Safari displaying a web page that has an image map with a tooltip associated with the mouseOver event of the <area>.

The iPad Safari browser clearly was responding to both fingerDown and fingerTap, and in different ways. When I tapped an area of the image-map, the tooltip that was connected to the mouse-hover event was displayed, and remained visible. When I held my finger down on an area of the image-map, the area changed color. So there's a 'finger-down' event somewhere.

QUESTION: Why isn't finger-Down the iPad-Safari counterpart for mouseOver? It seems a more likely candidate than Tap when mapping the mouse events:

MouseClick : FingerTap (i.e. finger down and then immediately up)
MouseOver : FingerDown (finger down and stays on the spot)

If the tooltip had been displayed upon FingerDown, it would have been able to be removed on FingerUp (i.e. counterpart to mouse-out), which is the typical behavior.

Could someone please enlighten me about the thinking process that led to these (IMO unintuitive) mouse-to-touch event-mappings?