It would seem the upcoming Gran Turismo on PS4 won't be called Gran Turismo 7 after all, but rather the more reboot sounding Gran Turismo Sports.
That is at least what the game is being called by Sony's Croatian importer Sancta Domenica, as reported by fansite GT Planet. Furthermore Sancta Domenica is already accepting pre-orders for the game, and as this company is the sole importer of PlayStation products in Croatia, Bosnia and Herzegovina the rumours have a certain validity to them.
Hopefully this will all be cleared up next week, during E3 in Los Angeles next week.