Over 120 new cars have been added to GT6, bumping the total to nearly 1200. You can see all the cars here. In addition, there will be over 100 layouts to race through across 37 locations, including new tracks like Mt. Panorama, Silverstone, Brands Hatch, and Willow Springs Raceway.
Of course, Polyphony Digital is also planning on supporting the game with post-launch updates. New tracks will be added, including "first-in-the-world" events. You can also create your own tracks in the Course Maker. With GT6, you'll also be able to use "GPS Logger" to create tracks based on your real-world commute by using the built-in GPS on your phone or tablet. That's a feature that will come in a later update.
Perhaps one of the best examples of Polyphony Digital's obsessive attention to detail is the promise that the position of stars are also accurately recreated for the game's real-world tracks. "On night tracks you can enjoy a simulated night sky with accurate positions of the stars and constellations. You can watch the passage of time, with the moon and stars moving across the night sky as you would see in real life," Polyphony promises.