It would've been much more interesting if they had entered some moral slippery ground in the Megaton-bomb quest.
For example, you could show Megaton off as a cesspool of corruption and amorality, enter an occasional murder, perhaps a scripted lynching, lots of theft, lying bastards, quests that are much more dangerous than you thought and so on. Basically, make the player hate the settlement. And then see whether the player can resist pulling the trigger when some 'bad guy' offers the means to blow up the town.
Well, really, is he, Burke, still a bad guy in such a situation? He might have his own agenda and plans, but in the end it will be you who will carry the burden. You won't be the mercenary hired to blow up the town anymore, even though you'll probably still get money for it. The money becomes trivial. This makes the dividing line between good/bad a lot fuzzier, and makes it depend a hell of a lot more on the player. Questions like 'who am I to judge these people?', 'even if they're bad, does that make it 'good' to blow them up?' and so on suddenly enter the arena.
But this doesn't fit with todays black/white dividing line that is prevalent in gaming. It even doesn't fit with the 'karma' system that is in place now, because this karma system is an artificial system of judging the player, while only the player and the world he plays in should be the ones judging, not some statistic. After blowing up Megaton it should be the consciousness of the player and the reactions of the other inhabitants of the world that make you feel either (self)righteous or guilty. The sharp black/white line is becoming more and more a bother in games nowadays forcing you to act in a certain way. It is like a divine being continuously judging your every move, while only you and the world are your judge.
I'm not denying that this might be in the game, but right now it just looks awfully shallow.
Edit: Oh, something I forgot to mention. The game's models and animations aren't helping either with the scenario listed above. If cardboard boxes are talking to you, you could care less about their death or lives. The other way around would also be interesting, have the player bond with Megaton, make it a heaven on earth, a utopia. And then enter the villain with an immense reward. But again, if all you see are rocks with mouths that occasionally try to utter words, you won't care. Morrowind and Oblivion never made me feel like I should care and I doubt Fallout 3 will achieve this.
