The blue scroll bars with the arrows at either end are gone. At first glance, it looks like there are no scroll bars at all.
In fact, the blue scroll bars have been replaced with iDevice-style scroll bars. If you don't know what these are, they are thin grey bars that that show up when you scroll and fade away when you stop scrolling.
On the iDevices (iPhone, iPad, etc) these hidden scroll bars free up necessary screen space. Macs don't have the need to save every pixel possible of space. Instead, the hidden scroll bars are part of the minimization of the OS X interface that is so much of Lion's style.
For many years, every Mac has had the ability to scroll using their pointing device. On a trackpad, you put two fingers on the trackpad and slide up or down. On the Magic Mouse you move up and down with one finger on the surface of the mouse. A Mighty Mouse has the tiny roller ball for scrolling. Apple has decided that people don't use the mouse to drag scroll bars any more or use the up and down arrows. I'd agree that this is true for most people. If you aren't one of them, it's time to move to trackpad or mouse scrolling.
The biggest downside that I see to these new scroll bars is that you lose the visual cue that tells you where you are in the page.
"Upside Down" Scrolling.
There are two different way to look at scrolling direction. Since the dawn of time, you click the down arrow of a scroll bar or drag the scroll bar down to move down on the page. You click the up arrow or scroll up to get towards the beginning of the page. It makes perfect sense.
On a touch screen device, however, scrolling is reversed. To move toward the bottom of the page, you slide your finger up. To move towards the top of the page, you slide your finger down. This makes perfect sense on a touch screen. (If you don't believe me, grab your phone or tablet and try it out.)
I use the iPhone and the Mac all the time, and I never once noticed that scrolling was reversed between the two.
Apple did notice, and part of their philosophy of bringing iDevice features to the Mac, they have decided that the touch screen way is now "natural scrolling." Natural scrolling is turned on by default.
Natural scrolling is very disorienting at first. Many people turned it off immediately. In the interest of science, however, I left it turned on to see if I could adjust to it. For me, it took a bit, but it soon started to make sense. Slide up to move the screen up. Slide down to move the screen down. The trick seems to be to completely ignore the scroll bars because now they are moving in the opposite direction.
I am using the trackpad on the Macbook Pro. I haven't had a chance to use natural scrolling with a Magic Mouse. I can see though that you might want to turn off natural scrolling with a mouse, especially if you use other computers. I'm not sure my brain could handle scrolling one way at home and the opposite way at work.
Turning off natural scrolling is easy:
- Go to System Preferences under the Apple Menu.
- Go to either theTrackpad or Mouse panel.
- On the Trackpad panel, go to the Scroll and Zoom view and uncheck "Scroll direction: Natural".
- On the Mouse panel, uncheck "Move content in the direction of finger movement when scrolling or navigating".
Like so many other things, your choice of scroll direction is entirely yours. But what the heck, you might as well give it a try– you might like it.