Yeah, they did a great job with it. I played for a couple hours last night.
Impressions:
-Cars are harder to drive, but this is good, slightly more realistic. You actually have to use the brake to make turns, and the ebrake WILL lock up the tires. Damage is more extensive, as Tom said. If you crash, it'll take out the lights, or even leave dents in the specific location you hit something.
-Hand-to-hand fighting is WAY better. You can push, punch and kick, as well as dodge and use counter attacks. It's not just button mashing anymore, in fact I nearly died a couple times in melee because I didn't know what I was doing. Also, if you start beating up a guy on the street, other bystanders will come to his aid and attack you.
-It seems that if you bring a vehicle to a mission, and are forced to take another, the vehicle you originally brought there stays nearby when you are done. I found a couple sports cars, then was mad when I had to leave them behind. Thankfully they were still there when I was done with the mission. In the starting apartment you even have two curb-side parking spots that will save your cars.
-I LOVE the new system for getting away from the cops. Instead of just painting your car or picking up little wanted level icons, you can simply get far enough away from the cops and stay out of sight for a while. They also mentioned that you have to be out of sight of the cops to use the Pay 'N' Spray, which is excellent, it was ridiculous to be able to come flying into them in Vice City with the cops on your ass, only to have them ignore you after the doors closed.