This was the case here in Australia anyway, but I'm sure it applies in a lot of other areas.
Surely this could be the case for the suburbs too? A whole suburb taken over by people doing startups would be an interesting place.
Artists/startups wanted to be located in the city and close to the things they needed because, as with wanting cheap place to live, they didn't have money for cars. The majority of these now abandon suburbs were entirely designed to be used by cars. They are bedroom communities with nothing in or around them but houses, and poorly built houses at that.
I think the issue really is critical mass - Access to the city is great, but I think what is required most of all is access to like-minded people. If you get enough of that going, then the rest will (generally) come.
... All that said - I get your point - even these areas had something going for them (e.g. the environment, surrounds, etc, etc).
On the energy conservation note - Does anyone have some quick tips for how best to utilise / retrofit a water tank? Last winter we filled an (existing) pool with rainwater - and now I need to do something with the pipes...