Just remember that if you declare non-residency, you may lose some Canadian privileges when you return. Most notably, if you are planning on attending University when you get back, you may ineligible for Government grants and scholarship (I know this is the case for Ontario, where you need to be a resident of the province for the last 12 months to be eligible). Also, many of the Ontario scholarships and bursaries are determined by your OSAP eligibility. So beware if you plan on attending Uni upon your return to Canada.
I personally made sure to have as many links to Canada (Car ownership, permanent address, investments (TFSA, RRSPs, Savings)) in order to keep my residency. I will gladly pay the government my due on my Foreign income (salary) and pretend I never left the country. BTW, if you are worried about paying taxes, you can offset it by buying RRSPs to the tune of 300$ return for every 1000$ you put in. (It's too late to contribute to the 2011 tax season though - you have the first 60 days of the year to do that - but it's early enough to start thinking about next year!
Cheers,
J