I'm playing a new game, which isn't bad, but I can't enjoy it much. The game is using mouselook, that is your cursor is fixed to the middle of your screen and whenever you move the mouse, you move the camera. You walk and shoot where you are looking. And that causes me video game motion sickness, also called simulator sickness, after half an hour I get nauseous and have to stop. Apparently that is something that happens to a lot of people, although the only data available are about military flight simulators used by the air force. The reason for the sickness is that your eyes tell you that you are moving, while your bodies motion detectors (in the inner ear) tell you that you are stationary. The conflicting information causes the nausea.
Obviously if your games make people sick, they aren't likely to buy them. So what can game developers do? A scientist studied the matter in detail, and came up with a "rest frame theory". Simply stated, you get less sick if there is a point in the middle of the screen that isn't moving, where you can rest your eyes. So third-person is good, first-person is bad. And of course the less hectically the camera moves, the smaller the problem. Games without mouselook are better, because if you can move the mouse to aim without moving the camera, your view remains so much more stable. I have no problems whatsoever with third-person games like World of Warcraft. But Morrowind and Oblivion I just couldn't play.
I really wished that game developer would make mouselook at least just optional. I don't see me buying any games that use it. How about you?