Honestly, we all knew Im@s PS4 was being made, they said that at... uh... TGS last year? Or something? The trailer was only a few seconds long, and mostly said nothing but, "Hey guys, we're making this game and stuff. Remember? No? Okay, here you go."
... But it did give us a few juicy morsels to party on. Rendering engine is different - my memory might be a little fuzzy, but I remember a more pastel look. I remember thinking it looks slightly hand-drawn - edges were softer, but had some texture to them and I thought I saw a paper-like texture being (very faintly) blended on to the scene. Think Valkyria Chronicles, but not as dramatic.
The models didn't look reused, even if they look kinda the same. Heck, they could have altered the ones from OFA for all I know, but they seem fresh.
But once again, my memory could be a little fuzzy. They'll probably show it again (or another) today.
The animations... or what little they showed of them, look smooth too. No nowano sightings during the PV though, and Haruka stayed on her feet the entire time.
EDIT: Saw the trailer again today, and the effect I thought I saw was only there because of the monitor it was being shown on.