LED streetlights will surely mean you can keep lights on in towns and residential areas, with minimal power consumption. I accept that in some areas, more rural, people are used to it being dark as it always has been. Imagine people who are used to walking home late at night, suddenly expected to carry a torch or now be forced to take a cab as it's too dark (and dangerous) to walk through certain streets.
I've replaced nearly all our bulbs (regular fittings and MR16 Halogens) with LEDs and they're great - although the MR16 bulbs are a little dimmer that I'd like. The Philips LED bulbs, many dimmable too, are awesome. Better still, they now have warm white options so you don't get the horrid cold/blue light from earlier lamps.
Even if we had all the lights on in our house, we physically couldn't consume that much power even if we wanted to!
LEDs have advanced so much I am sure the maintenance for LED street lamps would be minimal, plus if you had solar panels you'd probably be able to run them almost exclusively without mains power.
The downside is they're expensive, and local councils seem to be investing in the latest generation of high pressure sodium bulbs that are probably not very energy efficient at all.