At some point in our lifetime we may become responsible for our own power generation. Under this scenario DC makes much more sense as transmission over distance would not be an issue.
John, there is a house mid-way between yours and mine which generates more energy than it uses. He currently makes about $1,000 a year off the power company. This is the sort of thing I foresee becoming more common.
Mission Zero House:
Mission Zero House Old West Side Historic District, Ann Arbor, Michigan
I had a chance to see Matt's presentation at the local builder's association a few weeks ago (BRAG), and spoke with him last week on his front lawn. What he's done is not rocket science by any stretch, but it does take some up front money.
He did say in his presentation that compact florescent light bulbs will soon be replaced by LED's and other technologies. He referred to CFL's as the 8-Track tape of the lighting industry.