Valve have launched the offical Half-Life 2 site for viewing by the public. While the site contains no new information, a matter of hours away from E3 it is, a dedicated, official information source has pleased gamers nonetheless. The site also allows you to sign up for the Half-Life 2 newsletter.
Some users are still seeing the old website at the domain with information about Half-Life 1 and Counter-Strike: Condition Zero. If this is you, please be patient and wait for your DNS to update.