I don't think there ever will be a computer powerful enough to solve such a large scale planning problem. On top of that, I don't think it is even possible to get the data for it. Each person has his own personal "utility function" which he is trying to maximize and it is locked inside his brain.
It may be dated, but some writers and economists hold that people aren't even consciously aware of their own preferences. So even if you could gather the data from what people way they want, there would still be error.
One of the most colorful examples of this comes not from economics, but a strange book on advertising called "The Hidden Persuaders". It also talks about erotic images airbrushed into the ice cubes of whiskey ads :) When I'd first heard of "Mad Men", I'd hoped it would be about that, but it wasn't.
