I'm unfortunately prepped up for a big disappointment with Fallout 3. Bethesda has always made diplomacy and character interaction a useless notion in their games, relying mostly on finding the heaviest stick to crack someone over the head with. Sure, diplomacy is somewhat meaningless in the world of Terminator, but in the world of the Elder Scrolls, it should have played a bigger part. The World of Fallout had quite a bit of diplomatic leaning to it.
Fallout's best strength was that when you made a character, the character felt unique and able to do a set series of tasks. Sadly, Arena, Daggerfall, Morrowind, and Oblivion's only choices were to kill someone with a knife, an axe, of with spells. No matter what, you were just a cheap mercenary doing menial tasks. Sure, in Fallout you can be just a gun-for-hire, but that isn't the only way to play, which made the whole game unique. Hell, I think in Fallout 2 you can beat the entire main quest without spilling a drop of blood with enough diplomacy and sneaking skills.
While the notion of child killing being removed is a minor facet, it did have a certain flavour for the game. First off, if you get the "Child Killer" tag, then NO ONE likes you. Slavers and bandits will kill you, guards will kill you, civilians will kill you. You become a pariah. I liked this notion, as it gave a huge punishment for doing something so inhuman. Part of the game's beauty was that you could become cruel and evil, but if you do, then you will be punished. However, can easily beat the game doing cruel and evil things. Unlike many modern games where good and evil is, as Yahtzee put it, "Mother Teresa and Baby-Eating" the difference between good and evil was so much more grey. You could improve the bigger city by removing a smaller town. You could save the smaller town by sabotaging the bigger city, or you could try to make them come to an agreement, but sometimes that isn't the best route.
Bah, ah well. I'm sure the game'll sell well.