Last year, during the G20 session
in Toronto, the ground shook. I first wondered if some political bombing or
subway crash had occurred. News sites seemed jammed...but Twitter started
showing an increasing number of people asking "was that an earthquake?"
and "did you feel that tremor, too?"
Within three minutes I knew that indeed an earthquake had occurred, with the
epicenter in Quebec just outside Ottawa and that it had been felt as far east
as New York City, as far north as Barrie, as far west as Detroit and as far
south as Baltimore, just because I could see the tweets of real people in real
time.