Anecdotal, but I've had 20 (!) friends leave Vancouver over the past 5 years. 18 of them had young families and sought situations where they weren't grinding themselves into dust to make it work in a city/province that didn't appear to want them. 2 sought better professional opportunities in Toronto.
Totally a poor source of data, but i'm presently shocked by the number of my friends moving to the west coat. I decided id spend the summer in Victoria, and it appears 4 other friends, without having discussed it with each other are also doing the same thing.