Fallout 3, "Broken Steel," hits Xbox 360 and PC in March, it will replace the game's current ending, which doesn't allow players to keep on exploring the Capitol Wasteland post "end-game." This is something we've known since last November; what we didn't realize is that PS3 players -- already missing out on any DLC action -- will continue to be stuck with the current "brick wall" ending.
When asked by MTV Multiplayer if there were plans to patch the PS3 version of Fallout 3 for end-game play, Todd Howard, the game's executive producer, responded, "Not at this time, no." Howard has also remarked that Bethesda "really underestimated how many people would want to keep playing [past the ending]," and that Fallout 3 was "probably the last time we'll do something like that."
Source - Bethesda Won't Commit To PS3 Fallout 3 Getting Ability To Play Post-Ending [MTV Multiplayer]
Source - Bethesda Reacts To Three Major Fallout 3 Criticisms [MTV Multiplayer]