Australian gaming website, Gameplayer, has posted a huge 10 page article on their hands-on time with GTA IV. No big new information is revealed, however, it is all described in great amounts of detail. Here's their summarization of details from the end of the article, some you may find new or interesting:
Explosions are extremely robust and pretty. When we shot down the helicopter, the ball of flame lit up our screen and made a thundering bang before being swallowed in a cloud of black smoke.
Car damage is quite awesome, from bullet holes in the windscreen, to popped tyres sending sparks flying into the air and damaged bonnets flipping overhead at speed to go spiraling into the crowd.
In the mission to Live and Die in Alderney, Frankie could have died. We were under no obligation to protect him and had the A.I got lucky he may have expired. This would have affected future dialogue streams, but not the mission. So characters can die if chance doesn’t favor them and the game is prepared to deal with such an event.
There are so many dialogue streams in this game it is unbelievable. You can learn so much about the characters just from the way they talk shit to each other when nothing else is doing.
Jacob the Jamaican pot dealer’s accent is so thick and munted you can barely understand a word the dude is saying.
Niko was offered drugs twice in our play through, but denied them on both occasions.
We caught a brief glimpse of one of the safe houses in the game. You can change your outfit there should you please, although the options are based on what Niko would realistically wear (i.e. no chicken suits).
During the mission Harboring a Grudge we engaged in a massive shoot-out down at the docks. It occurred during a thunderstorm. The rain looked quite awesome as it bucketed down, but it was the lightning that was most memorable. As it cracks a flash rattles through the whole world, throwing its own weight behind at atmosphere already encouraged by the bursts of fire coming from everywhere and the environment falling to bits under the combat.
There is a definite shift in skill level of the A.I as you go up the chain of the law. Get caught in the open while fighting the Feds and expect a head-shot.
When you die, the screen fades to black and white and the camera shifts to a first-person view of your final resting place – it is quite affecting, and again, not a small bit cinematic.
A big head-on crash will cause you to go flying out of the windscreen to serious injury and possibly death: Niko ain’t got time for seatbelts.
Jumping out of a moving car can create a truly awesome ragdoll/Euphoria effect that makes Saints Row’s insurance scam missions look like a piss-weak joke. We wasted a good ten minutes just laughing our arse off driving into busy areas at full pace and then bailing out the door.
Niko likes the ladies.
Source: GTA Gaming