Grand Theft Auto IV

GameSpot
News, previews, images, videos, links, and a forum.
http://www.gamespot.com/ps3/action/grandtheftauto4/

GameSpy
Provides information and news.
http://xbox360.gamespy.com/xbox-360/grand-theft-auto-4/

IGN
Screenshots, news, features, and a message board.
http://xbox360.ign.com/objects/827/827005.html

Team Xbox
Provides news and release data.
http://games.teamxbox.com/xbox-360/1482/Grand-Theft-Auto-IV/

Wikipedia
Article describing episodic content, controversy, and trivia.
http://en.wikipedia.org/wiki/Grand_Theft_Auto_IV