MacOS – assign Magic Trackpad 3-finger swipe up/down to scroll to top/bottom

Solution: Go into settings -> trackpad -> turn off the four finger swipe, and turn it on again.

(Credit to Stiwi for the very efficient Jeopardy Question)

This may be one of those things that is labeled as a "feature not a bug." It's possible that the swiping gestures that are the same as the gestures on Snow Leopard are considered "Legacy" gestures. If that's the case then it is possible that having it "backwards" Is the expected behavior. If it's a legacy gesture then it may be considered to ignore natural scrolling because that is a "new" feature. I'm not saying that's how it should work, if you ask me if you change the direction of scrolling, it should apply to all gestures, not just the scrolling ones. I've moved mine back to the two finger option for the moment. You should file it at http://www.apple.com/feedback to make sure that Apple knows how confusing this is.