UPDATE III. A change of view in Toronto:
Hilariously, the decline in support for the no-power-hour seemed to disappoint Earth Hour booster the Toronto Star, which, full of hope and wonder, published the headline “Toronto goes dark for Earth Hour,” only to update the article two hours later with the headline “Toronto stays bright for Earth Hour.”
A possible reason: ignited cats.
Go here http://blogs.news.com.au/dailytelegraph/timblair/index.php/dailytelegraph/comments/one_reason_to_support_earth_hour/ to find out about the singed cat/Earth Hour connection.