In that video it looks like safari now auto hides the scrollbar when it's not being used (kinda like on the iphone), seems like an odd thing to do, since 20px of screen space isn't as precious on a desktop as it is on a phone.
I don't think saving the screen space is really the point.
It's more likely about reducing the amount of clutter on the screen. If you don't need something, why put it on the screen? Apple's minimalist design strikes again.
The question is how to display things like that on a desktop OS that might be used with a mouse. With a touch gesture, you touch and then move vertically as a continous action. On a mouse, you click or turn a wheel, much more discrete actions.
Edit: Aha, they addressed this: "With the new scrollbars, if all of the user’s pointing devices support both horizontal and vertical touch scrolling, the scrollbars are hidden during normal use. They will appear as an overlay on top of the window's content while the user is scrolling, and remain visible briefly to allow scrollbar dragging."
"Mac OS X Lion introduces overlay scrollbars similar to those in iOS. These scrollbars appear as an overlay on top of the window's content while the user is scrolling and remain visible briefly to allow scrollbar dragging."
Do you read that to mean that all standard Aqua scrollbars will be rendered as overlay scrollbars in Lion? My initial impression was just that the overlay version will be made available to developers. That said, some OSX apps already use them, so I'm not sure why it has been highlighted as a new feature of Lion... any thoughts?
