As alluded to earlier, the whole concept of free running is fairly fundamental to the gameplay too - and, again, Ubi has changed the control emphasis in a way that makes it feel initially unfamiliar. For example, there's an unwritten expectation on the part of the player that you need to press buttons as well as the direction to perform actions, such as jumping or climbing.
The way Ubi has found around this is to simplify things dramatically with its free running concept. Essentially, Altaïr automatically navigates everything in his path by holding down the right trigger, pressing A and moving towards whatever obstacle is in front of you, such as large gap, or climbing up a wall. Once you start the action, you can let go of the right trigger and keep on bounding or climbing without the need for further button presses. Instinctively, you'll want to haul yourself up ledges, or press jump to get across a gap, but that's all been taken away. You'll still make those imaginary presses for hours afterwards, but that's gaming conditioning for you. Old habits die hard.