I actually like the idea of using my TFSA as my "retirement fund" and use my RRSP to help with tax avoidance.
I am fortunate enough that I am able to max out my RRSPs and TFSA, (plus add to non-registered account), but how I plan to use each:
Non-registered - used for continual growth (compounding, yay!) and will be part of retirement income
TFSA - used for retirement income (I won't take any money out of this one, just let it grow and keep adding as much as I am allowed to.)
RRSP - will use for special requirements where for instance, the wife goes on Mat leave - she can withdraw from her RRSP since her annual income will be a lot less, we can get a lot of the taxes taken off the withdrawal (under $5000 each time) back at the end of the year. We also have the RRSP there in case of extended unemployment for us. And in the good years, our contributions help lower our taxes.
I figure that's a solid plan, but I'm not a financial advisor at all.