So, according to the details coming from the Official Xbox Magazine, The Pitt will be set in Pittsburgh and it consists of an abandoned steel yard (apparently a dungeon, of sorts) and a settlement divided between the slaves in Downtown and their masters in Haven. The surprise comes from the fact that you’ll now infiltrate the Raiders bands in a quest to reach their leader who might have found a cure for mutations.
There will also be some side quests brought by The Pitt, but we have no details on them. However, we do know that an extra item called the AutoAxe will be introduced (but there might be more), as well as three new perks and a new population of mutants. So, as I was saying, this upcoming DLC episode for Fallout 3 will be pretty solid. For Xbox 360 and PC owners only, coming this March.