Graphics taking a backseat to the story would be awesome. I think indie games are showing that gamers don't care too much about graphics as long as the gameplay/story are good.
I'd love that as well. But what does Valve has anything to do with it? If it's an open platform, it probably isn't a good idea for them to tell developers to do it their own way. It's up to the developers to decide that.
Indirectly thru the values of this Steam box. If most of the hits on this box are not graphic rich but very gameplay or story rich + hardware is mid-range + shiny tools for story, AI and multiplayer it will inform developers to most of their games in one way.
I second this as well. I think the spot light on eye candy due to mass appeal, for the past few years, has shifted the focus from game play it self which is what games are really about. I'd take a clever and fun game over a glossy one any day.