Priced at 800 Microsoft Points ($10), the download, dubbed The Pitt, will allow players to explore post-apocalyptic Pittsburgh, face some moral quandries regarding slaves and Raiders, and wield a kick ass serrated rotary blade known as the AutoAxe.
A third bit of Fallout 3 downloadable content, Broken Steel, will be released for PC and Xbox 360 players in April. In addition to raising the game's level cap from 20 to 30, Broken Steel will also continue the story past the original ending.
but i still haven't finished the main game :(
Where are you in the plot? You might not have that far to go.