There is no doubt foreign wealth is driving Vancouver's and now Toronto's housing markets. They wouldn't behave like they have been without major outside influences.
In Vancouver's case, the market suddenly took off in 2002 - house prices doubling by 2006. This was after 6 years of correcting downward by $50,000 from the Hong Kong takeover peak in '96.
For a no BS explanation for Vancouver's housing market since 2001 from quite a reliable source, Google 'kim marsh rcmp 9/11'.