The game will naturally feature improvements to the gameplay, including but not limited to new tracks, new cards, an overhauled user interface and a new game engine. The cars now total over 1,200 and the tracks now number 33 and 71 different possibly layouts. More cars and tracks are already promised to be released as DLC after the game's launch.
Enhancements and improvements also extend to a much-improved course maker function, which will provide several kilometers of gorgeous scenery, including the magnificent backdrop of Andalucía. The course maker will also include a new GPS data feature, which will increase the freedom of track creation in the game.
More information on GT6 will be revealed during E3 and Gamescom in the coming months.
(via PlayStation blog)