Raw prices don't tell the whole story, affordability takes salaries into account.. who cares if a house is twice as much in place B if the salaries there are three times higher?
I don't really care much about the actual value of the real-estate in value terms, I just care if the prices are going to go up or down based on demand.
Affordability in Calgary and Alberta has gone down over the past few years of course, but it's comparable to Toronto and of course way higher than Vancouver. Heck even Saskabush has seen the affordability go down to Alberta levels.
Of course there's places where it's much more affordable to live, but I can also take a look at other cities and find places globally where affordability is far worse.
EDIT: Oh and I totally agree with the renting vs owning, there are situations where it is better to rent for sure. But many people own because of other considerations (want to do their own thing with the place etc).
And RBC's stuff on affordability across Canada:
http://www.rbc.com/economics/market/pdf/house.pdf
If you look at housing prices as a multiple of annual income, Calgary is well below the national average in Australia and New Zealand, below the UK, and there are many cities in the US that have far worse affordability.
http://www.normfisher.ca/pdfreports/dihas2008.pdf
All I'm saying is that big picture it's not like things are so far out of wack that it's going to crash to a halt, at least not on the basis of the cost of housing itself (as shown that there are places that are far less affordable).