It doesn't look pre-rendered to me at all. People are walking but no real time sand deformation? Girl with sunglasses is walking but no physics on necklace? Mr muscle man is jogging but he looks like a plastic model? In fact the skin shaders are pretty wrong. There's no translucency. They're on the beach yet there's absolutely no wind? Umbrellas are pretty static. The building geometry is pretty basic, even games AA games like robocop shit on it from a great height. I've watched the trailer several times and the only impressive parts are the density and simulation. From what I've seen, if this were to release right now, it can't even crack the list of top 5 best looking games.
Edit: Here's an image of a crowded beach in Miami. Noticed how all the people haven't been baptized by a priest in oil. Look at the skin, look at the sand, then compare that to the game. Not even close.