The scroll bar numbers make me further believe that OS X Lion's scroll bars are a bad design. My computer is not a tablet... saving ~10 of 1920 pixels is not something I needed or wanted.

What jumped out at me was the 71% for the reload button. Unless they've changed the layout since I customized my copy, the reload button defaults to being a tiny button at the right end of the awesome bar. I moved mine to where Chrome has it and these numbers indicate that a lot of others have done the same. That or Mozilla moved it and I naturally didn't notice.

Ubuntu Unity has some neat tricks to make scrollbars more usable [1]. Instead of requiring users to hone in on the up/down arrows or the "thumb", hovering anywhere near the scrollbar brings up a widget that compactly encapsulates all this functionality. I don't care for Unity enough to start using it day to day, but this feature struck me as clever though radical.

Yeah, don't people use their mouse wheel or two finger scrolling on the trackpad?

I notice this all the time with your 'normal' user. The scroll bar is quite possibly the most horrific unfriendly control. It's just too narrow. Those users that don't have that much control of a pointer, struggle with scroll bars and small buttons / drop downs etc.

I like the Apple way of placing controls on the left, but having a scroll bar on the right negates a lot of the benefit of doing so.

Having said that they are quite handy as page length / where you are indicators.