Well, that, in itself, says something about how effective the event was/is/will be, and how much media and public attention it gets.

I. myself, learned about it from my LJ f'list first, particularly indefatigable42 and nexstarman. Then, on Friday night, there was a brief (30-second, maybe?) mention of it on one local news station, about a local restaurant joining in.

Here is a Wikipedia article about the global event (http://en.wikipedia.org/wiki/Earth_Hour)