The lucky bastards (just kidding guys!) at Kotaku where one of the sites to post their impressions on their recent test run of the Grand Theft Auto IV multiplayer mode. They summed up just the facts for us guys who don't really want to read a lengthy post. View that below.
Grand Theft Auto IV Multiplayer Fact Sheet
Supports up to 16 players in all adversarial modes except co-op, which is a maximum of 4
Players are ranked from 0-10, picking up money in multiplayer increases rank
Options in each mode are dictated by the host - among the options they can change are location of the matches (can be entire city, one borough at a time, or even small sections within the borough), types of weapons available, time of day, weather, use of auto-aim, police presence, NPC presence, and tons more.
GTA Race sees the host choosing the class of automobile, each player can choose a car within that class. Races can include helicopter and boat races as well.
Classic deathmatch done Grand Theft Auto style. Go anywhere, do anything: the whole city is yours. 16 players max, teams can be made in any configuration. Weapons on the ground can be configured by the host. Capitalism rules here: the team with the most money in the end is the winner.
Rockstar North's twist on the concept of a race. Host selects vehicle type (each racer selects his or her specific vehicle after that), race, number of laps, and time limit. Despite ordered checkpoints, players can go anywhere in the city at any time. Do you want a straightforward race from start to finish or do you want to create a roadblock and shoot rockets at your fellow racers? The choice is yours - each player does it slightly differently. 16 players max.
Cops N Crooks
2 teams, 2 vastly different goals. The cops can see the crooks on their radar but the the crooks can only see the escape point making this the ultimate cat and mouse situation. For the first time, players can get a chance to be on the other side of the law in a Grand Theft Auto with Cops n' Crooks. A team of "crooks" need to get their boss to safety, as the team of "cops" pulls out every trick in the book to try and stop this from happening. Again, 16 players max.
Co-op in Grand theft Auto IV is a 4 person affair. Each mode is a short, story-based mission you must complete with your friends. In Hangman's NOOSE you must get crime boss to an extraction point alive. First, several of Liberty City's finest need to be dealt with and then transport must be secured. Will you take Kenny to safety in an armored car? How about a motorcycle or attack chopper? The choice is all yours.
Remember, these multiplayer modes are just four of the fifteen gameplay modes to be featured in Grand Theft Auto IV. 21 days.
[GTA Multiplayer: Just the Facts Please]