GameSpy has the first online preview of Resurrection of Evil, the Nerve Software developed expansion pack for DOOM 3. The article offers an overview of new features and content, quotes from id Software designer Matt Hooper and two screenshots. Here's a bit on the artifact that starts the story for the expansion.

While DOOM 3's Soul Cube was the ancient civilization's ultimate weapon against the forces of Hell, this artifact was Hell's counterpart... and they want it back. Bad. "It's Hell's ultimate weapon," Hooper explains, "and you have to get it to the surface." This artifact and the three demons -- called "Hunters" -- represent a central component of Resurrection. Each of the Hunters has its own special ability, and the artifact is able to "steal" these abilities once each Hunter is defeated, so you can add it to your own arsenal. The first Hunter has an ability called "Hell Time," where everything in the world but you slows down. There's an obvious parallel to "bullet-time" from the Matrix movies and the Max Payne games, although Hooper points out that it's not quite the same [...]

Update: IGN now has their own article about the expansion.