Well, I want to disagree. I think that thinking is the same thinking that gave us City Hall Plaza back in the day - simply put, I find it too visionary...
My proposed reality is this - the automobile is never, ever going away. Literally - never. Very little will change in the next 50 years. We may not drive gas-powered automobiles, they may drive themselves, they may be any number of different 'personal transportation pods' but 'cars' are not going away.
Removing cars from human life is a radical and wild concept that would uproot and re-invent literally the entire world. It is not going to happen in the next 50 years at least.
So my vision of the future is so much less bold - it's just like today, but with more conveniences. All social evolution has been driven by convenience. Rarely has humanity ever evolved in a manner that inconveniences people.
So I don't see people ever ditching cars for public transportation. So I think it's foolish to design for less cars in society.
We may limit and change our driving habits and vehicles over the years, but my big, bold prediction for 2058 is that we all have 'cars' and 'drive' to where we want to go. Just like today.
I've biked to work, it's fun. I've taken public transportation, I could see it working if I was closer to a stop on both ends. I've walked to where I need to go when the weather is nice and I want some fresh air. But nothing fundamentally changes the automobile society that we live in, and I think it's humorous for designers in 2008 to imagine architecture without the prevalent and heavy use of 'cars'