I've been living and working in Toronto since 2003, and can attest that it truly is a fantastic city to live in.
Most of the senior developers I know in Toronto work as independent contractors for large enterprises because they can get paid significantly more than the base salaries mentioned here. Contractor rates rival Silicon Valley salaries.
The downside of independent contracting is that you forgo sick pay, holiday pay, and employee-sponsored perks like extended health care. However, Ontario has an excellent public health system that covers all residents so the need for additional health benefits is questionable.