I think Canada is losing far more people to the US than the other way around, at least at the higher end of the market. Canadian salaries just aren't competitive at that level.
The US is the NBA, the stars definitely do go there. A pretty good life strategy is to work in the states from 30-45 while you're young and healthy, then come back to Canada for peace and safety to raise your family. I've seen a few people do that. I'm not sure it ends up being that bad for Canada. On the one hand they lose stars during their productive years, on the other hand they come back during their spending years with more money/knowledge/sophistication than they would have had.
Create a business != create jobs.
A large infusion of outside capital will boost a local economy. They will own homes and buy things from local merchants which will create jobs.
That is still lesser than the impact of entrepreneurs abroad. Ask the Canadian govt what they would prefer and it won't be suburban families. Canada will always be 2nd in technology.
