We've played through the first section of Doom 3 on Xbox - and it's one of the most atmospheric and, frankly, downright horrible games we've seen for an aeon.
In classic Doom stylee, the early tasks are very basic, with the focus mainly on blasting the hell out of the hordes of really unpleasant looking monsters with the aid of grenades, pistols and a handy submachine gun. The best tactic, wherever possible, seemed to be to blast at the oil drums littering the typically dark level, which sends off foes in a pleasing fireball. Alternatively, just shooting away at them invariably exposes their rib cage, which is just as aesthetically pleasing and equally gruesome.
Speaking of which, one of the grimmest in-game sights we've ever seen comes in the shape of one of the giant bald-headed humanoid enemies being crucified. On the ceiling. With a large portion of his internal organs ripped out. Mmmm.
Aside from the ace-looking enemies and classic Doom environment (very low lighting, narrow corridors), it's the sound that's really effective in pumping up the chill factor. With the Resident Evil-like groaning of the monsters, random shouts of "help me!" and the onslaught of explosions, it's pretty much the closest thing to hell you're going to get on your Xbox. And if that's not a recommendation, we don't know what is.
While the PC version of the game is now confirmed for a summer release, Activision are still saying that the Xbox incarnation will be released "when it's done". Whenever that happens to be, it should be well worth the wait.