Overall a highly entertaining debate especially the twists at the end, there's one thing I didn't really get though. Was that last minute swerve by Chris before they cut to the credits supposed to be a reference to something or was he just being random?
Video discussion aside, I find that in a game like Fallout 3 the matter of Good and Evil is not always so cut and dry if you get down into the nitty gritty of it. Take the supposed remnants of the United States government known as the Enclave, the faction in game is unquestionably painted as the evil one and the Brotherhood of Steel the good. Though their moral compass might have been removed or completely inverted the Enclave does have a noble sounding goal, the eventual restoration of the US to it's pre-nuclear war glory. The only problem is that they feel that for this to happen all irradiated inhabitants of the wasteland would need to die, which is pretty much anyone who is not in the Enclave. To some this may be perfectly acceptable logic when you consider the horrible state of the world and the scarcity of resources like food and water that isn't irradiated. But the game never lets you choose Enclave or the Brotherhood, no matter how many times you play the core game the enclave always loses in the long run even if you don't destroy their base or kill their most senior military officer. Even in the Broken Steel add, unless you sneak nearly everywhere you go you have to all but annihilate the last of the enclaves forces and only then do you get the option to use a satellite guided missile strike to either hit their mobile command post or destroy the Brotherhood's primary base in the Pentagon.
But that's just a sparse analysis of the two main factions in the game, some things 'I think' are unquestionably evil, like wiping out an entire town that has an undetonated 'megaton' nuclear bomb sitting in the middle of it because some rich asshole living in a tower thinks it's an eye sore.