The 2006 census figures just released show that 1% of people in the Greater Toronto Area get to work by bike.
With shorter trips and relatively more welcoming streets, it's safe to assume this number doesn't reflect reality for downtown cyclists. It would be interesting to see how this number varies throughout the region. Casually, I've heard that 5% of people cycle to work downtown. If that's true, the number of cyclists in the suburbs must be much less than 1 in 100.
I know I'm mixing anecdotes with real statistics here, but 1 in 100 is an amazingly small number considering how many people tell me they either do ride their bike to work or would like to but don't feel safe.
With cities like Amsterdam and Copenhagen seeing numbers in the 30 to 40% range, there's obviously a lot of room to improve.