Despite the fact that Hideo Kojima's big Metal Gear Solid V: The Phantom Pain reveal at GDC seemed to shed some light on the series' direction, it looks like there's still a bit of confusion. While Kojima made it sound like Ground Zeroes and The Phantom Pain were the same game, it turns out they're actually still separate titles.
According to Konami's Director of Public Relations, Jay Boor, "Ground Zeroes and The Phantom Pain are two separate games. GZ will be a prologue to The Phantom Pain."
That does somewhat elucidate Kojima's comment on The Phantom Pain being "a tutorial that starts from crawling."
When asked about the destination platforms for the pair of games, Boor couldn't say anything about Ground Zeroes, or if the two games would be part of the same package. He did, however, confirm that Metal Gear Solid V: The Phantom Pain is "definitely 360 and PS3."