Bug 829952 says that scrolling using the touchpad feels slow on some laptops.
Turns out that it’s quite hard to provide a consistent scroll experience on the various platforms which Firefox supports, due to many laptop and touchpad manufacturers, different drivers, OS configurations etc. We could have provided some (or a lot of) configuration UI, but the best solution would be to get it as good as possible out of the box.
And to do that, we need data - and you might be able to help.