The addition of better story telling in games is not aimed at a casual or hardcore audience. They're doing this, in their minds, to continue the evolution of games as an art form, not to adjust their target consumers.
At least on the developer side of things.
Publishers on the other hand, are starting to look at story in games as just another "value added" propositon.
Just like graphics, physics, easier to pick up and play, ect.
Check us out at the Vindication Gamer Network on Youtube.