Earthquake in Toronto?

Wow - The whole building just shook. I thought it was vertigo, but I went on Twitter and it looks like a whole bunch of people felt it.

Nothing at this Earthquake Forecast site yet, but should show up soon. [Update: Full information on the quake's specifics from USGS here.]

I didn't know Toronto was on a fault line. Now I see this from a CBC site:
Canada is a veritable hotbed of seismic activity. The country averages three to four earthquakes a day – more than 1,200 a year. The vast majority of them can only be detected by the sensitive equipment that measures seismic activity.

But – a few times a year – Canadians do feel the earth move. The most active parts of the country are the western and southwestern regions of British Columbia, including Vancouver Island and the Queen Charlotte Islands, which are struck more than 200 times a year. However, Eastern Canada has also been hit by major quakes, and experts cannot rule out a major earthquake hitting Toronto, Ottawa or Montreal.

Except for reports of one death in an earthquake in Montreal in 1732, nobody has ever been killed by a quake in Canada.

On Nov. 18, 1929, a magnitude 7.2 quake rattled the floor of the Atlantic Ocean about 250 kilometres south of Newfoundland, which was then a British colony. Nobody died from the quake, but 29 drowned after a tsunami swept across the Burin Peninsula.

G-20 related, or just random?