I've just got an email reply to a question I posed to Jim Kunstler, the guy you saw in the "End of Suburbia" DVD.
My question was : "... is the super-dense vertical suburbia where I live (Singapore, over 6000 people/sq km) any better or worse than America's horizontal suburban sprawl?"
Haven't got his say-so to post his reply in its entirety, but here are the main points :
1. Any building over 7 storeys is a product of cheap energy.
2. Paris and London are doing just fine with the low buildings they have.
3. The developed nations will have a problem with their electric grids ahead.
4. That's not too good for cities with tall buildings like New York City (and I suppose, Singapore too).