Been watching some PC streams of this and picked up on a couple of annoyances imo:
(no story spoilers here, just gameplay)
* Some cutscenes are unskippable - grrrrrr really bugs me that.
* The driving physics look pretty poor, vehicles are either stationary or at full throttle, they dont seem to be able to just cruise like GTA4 and they move like go karts.
However, the game does look pretty good on high settings (not sure if the stream was on high or ultra) but it did look very nice, especially at night and the water effects.
A bonus too which the player mentioned was you can toggle between walking or jogging and a separate key for sprinting. This I like as all the videos I'd seen previously was the player ran everywhere, this game is meant to have a stealth aspect to it so its nice to see you can just walk/stroll about.
Unfortunately there seems to be a lack of scripting sometimes too, if a hack is activated like the traffic lights and causes an accident the emergency services turn up but dont stop, they just drive past lol, unlike GTA. I watched one vid where the player hacked the traffic lights, cars collided and one blew up killing a pedestrian. An ambulance came round the corner with its lights flashing but just carried on driving past and didnt even stop. So the idea was there but it seems like an after thought to create some form of 'real world' NPC's but if its not followed through completely then dont include it. In GTA the paramedics stop, say something witty like "he's a goner" and drive off again. But at least they stopped lol!