Gran Turismo has always been the mac-daddy of SIM racing, though there are plenty of others out there, just less popular. Then Shift 2: Unleashed arrives, which decides to contend with GT5 over realistic car racing in game. But now there’s another that wants to take that throne away from them, and it’s none other than Forza Motorsport, and this time it’s the 4th sequel to the popular car racing game.

The newest installment of Forza leverages Kinect technology, allowing players to open the doors and hoods of their cars with hand motions and fire the engine from the driver’s seat. During a race, Kinect also lets players look around corners by detecting head movement.

Turn 10 says its goal is to produce the best-looking racing sim of 2011, employing methods like image-based lighting to get as much photorealistic quality as they can out of each car and track. Turn 10 also says that Forza 4 will have the most extensive range of models to choose from, with cars from over 80 manufacturers. The company is planning on shipping Forza 4 into your XBOX 360 in October. In the meantime, check out the “leaked” trailer after the jump.