When asked if the game was going to be released on the PlayStation 4, Sony's Shuhei Yoshida insisted that the game is a PS3 title, telling Eurogamer, "The game is developed on PS3."
So what's the hold up? According to Yoshida, "We had the game playable. At one point we felt that it would be produced for a certain time period. That was the time we prematurely talked about the launch window. But it turned out the technical issues are much harder to solve. So the engineering team had to go back and re-do some of the work they had done."
Somewhere along the line, however, the game's designer, Fumito Ueda, left Sony as an employee. However, he is working still working on the title in a contracted freelance capacity. Western studios have been brought in to finish the title.
Forget hearing that this is still a PS3 game, it's good to hear that this is still, well, a game.
Check out Kotaku's "eyes on" impressions of The Last Guardian.