They claim that the environment will be six times larger than San Andreas, with 350 different cars to drive, and would see players having to administrate fuel levels in their vehicles. Where they get their information is unknown.
Well what is Rockstar’s word on it? This morning they phoned gamesradar to inform them that the picture is not of any GTA game currently in development. While Rockstar has no idea where Jeux-France got the shot from, the company has gone on record to deny that the picture came from any of its internal development studios.
You'll no doubt be seeing lots of fake screenshots of the coming months, years actually. But rest assured when Rockstar release the first real screenshots we'll have them.