Here's a quick summary of some of the main points discussed
I. "Over 1,000 vehicle customization options"
II. Car will turn up in an impound if left in the street. Must pay a fine to retrieve it
III. You can't directly "weaponize" your car, but there are a lot of little options
IV. Guns will be with you throughout the whole game
V. Customized guns will broaden range of options during missions
VI. Quickly switch your focus to other enemies. No longer need to lock on to enemies, although you can lock on if you wish
VII. "Hits are much more satisfying"
VIII. Expect really cool destruction, carnage or damage
IX. Car horns can be customized