Well, that applies to pretty much the entire game, though, doesn't it? Sure, I'd like more interactivity with the NPCs, and more consequences to my actions (which is pretty darned hard to program - considering that since the very dawn of roleplaying games, players have been notorious for coming up with ways to blindside the GM.) But for what it is, it's still something that I thought brought something new to the table for the franchise. Before Fallout 3, it was always up to the players' own interpretation exactly what it was like to have grown up in a Vault. Now it's something that you're able to experience - at least to the extent that the game itself is capable of conveying.
Sure, I went in during my first playthrough being very careful of every single thing I did, thinking that at some point it might have further impact on how things would play out. And it didn't take long for that illusion to fall apart. But that's not really the point, either. I'm not talking about faililng to show the repurcusions of what you're doing as a character, or NPCs reacting to you in a believable manner. But just in terms of illustrating life in a Vault, I think that's something beneficial that F3 brought to the table.