I think that Toronto will likely develop into an increasingly unique urban form among North American cities.
I read in a Toronto star article that provincial and municipal legislation are encouraging greater and greater density. So TO will likely house more and more of it's middle class population in condos and other dense developments in it's core.
This is the right direction I feel - to not just make dense housing in the downtown core an option exclusively for the upper class but also make it the most viable option for the larger middle/working classes. This will certainly make TO stand out among the US cities which seem to only build dense infill housing for the elite (ex. Manhattan's density seems largely out of reach for a middle/working class family).
In the US single family housing is still the preferred option for the American middle class. It's very unfortunate.
I don't know when Americans will wake up and see that our single family housing tracts are resulting in a huge loss of valuable farmland, natural habitat, and more smog + traffic congestion.