For work:
Gamasutra - Pretty informative for anyone that is interested in the gaming industry
International Game Developers Association - Another useful site and organization for the gaming industry

For Fun:
GamingFM.com - Relive your console and PC games via streaming music
Star Wars Galaxies - the Star Wars MMORPG and their forums
ComingSoon.net - The reason I never rush to catch trailers at the theater any more