Frankly, I think its bullshit.
Don't get me wrong, power consumption awareness is a good thing. I just don't think turning your lights off for an hour teaches any lasting lessons.
As a reminder of "WOW am I ever thankful for electricity", it could work.
I have no intentions of turning my lights off or anything like that. I will do my usual thing during that hour.
This is not to say I'm not doing my part mind you. I just bought a Kill-a-watt meter. I want to get some idea of what the devices in my home are /really/ drawing, and maybe make some smarter choices about when my computers and other devices are on/off, etc.