From the looks of GTAV running on PS4 in that trailer, I'd bet it's 30fps. Metro Redux is nowhere near the same as GTA on scale and complexity, so it's a silly comparison. The 360/PS3 versions of GTAV could run at 60fps, but Rockstar is upping the graphics.
It's not a silly comparison because both games are very CPU bound.
We're really pleased with the performance from the two consoles," Beynon explained. "We thought it would be 30fps as it's a very CPU-heavy game so we're quite pleased to get the [dev kits] in the studio and get it to 60fps."
I don't see what would prevent 60fps other than choices. But it seems the overwhelming majority of console gamers don't mind 30fps so Rockstar may be tempted not to spend the engineering effort to get GTA 5 up and running at 60.
I have nothing against a rock solid 30fps but...I really prefer 45+ and higher. It feels much, much smoother to me.
I'm far from being a 60-or-nothing kind of PC gamer but I'm cognizant of how framerate dramatically alter the experience for the better.
I still genuinely believe it's possible for them to reach 60fps. Maybe they think it's not worth it and they will rather maximise the visual fidelity and settle for 30.Very different games, very different engines.
It's their call.