Similar to Criterion Games' Burnout Paradise (PS3, X360), the game seamlessly integrates online multiplayer with the single-player campaign through use of the in-game cell phone.

"After players earn the cell phone in the single-player game, which takes about five minutes, if they want they can jump online and never even play the single-player again," Rockstar development VP Geronimo Barrera told GameTap. "Online is a serious time sucker. You're going to have to be really careful if you're married."

Once players are online, they can engage in matches up to 16 players in a variety of configurations. The game supports the standard-issue team deathmatch mode which can be customized for team balance, traffic, police presence, and weapon types.

In addition to the previously detailed Cops 'n Crooks mode, Rockstar also demonstrated GTA Race, which is said to draw directly from the races in previous GTA single-player campaigns. 16 players can compete in an all-out deathrace using any vehicle available in the game, as well as a variety of weapons to trip up adversaries.

Hangman's Noose, meanwhile, is a collection of cooperative objective-based missions for four players versus computer-controlled enemies. The goals are generated randomly, tasking players with objectives such as surviving a massive assault from SWAT police while protecting a VIP from harm, and later escaping from the fuzz.

The game's fifteen-plus multiplayer modes are divided into ranked and unranked modes. While unranked makes for a less competitive experience, GTA 4 rewards intrepid ranked players with cash, which allows for more character customization options.

Grand Theft Auto IV is scheduled for release on both PlayStation 3 and Xbox 360 on April 29.