I go to this site at least once a day. It's how I stay in the know about the happenings around the world, though my biggest interest is usually the happenings in the Sci/Tech section of the site.
Otherwise known as Spawn.com, I go here on a daily basis, to the forums, where there are daily updates about exciting new stuff. PS: Ryan, they're making Texas Chainsaw Massacre (2003) figures.
This site isn't an official Maxis site, but it has a lot more information than Maxis. From the latest news to the latest screen shots from The Sims 2.