"It'll be GTA Online; it's not part of GTA 5," Rockstar North president Leslie Benzies told CVG. "Obviously it's set in the GTA 5 engine, but it's going to grow and evolve into its own thing."
"Access to Grand Theft Auto Online is free with every retail copy of Grand Theft Auto V and launches on October 1st."

http://kotaku.com/this-is-grand-thef...ine-1148134265