It varies from person to person, but it seems that for most people that if they have "jumpy" movement controlled by the player (ie in Half Life: Alyx you kind of teleport around) it avoids the motion sickness, but "smooth" movement (ie WASD or what you're used to in games) affects a lot of people. The killer for almost everyone is cutscenes - the Skyrim VR opening is horrible for motion sickness.