I'm sure glad I don't run a paysite in Canada.
Been doing some reading though, and for anyone else that might be wondering, it looks like plain old affiliates are still safe, as long as the program you are promoting is not based in Canada.
Some good info here:
http://www.cra-arc.gc.ca/E/pub/gm/b-...-e.html#P22_93
Example:
A non-resident person who is not registered for GST/HST purposes pays a fee to a registered Canadian Web site owner to place banner ads for its business on the Web site.
The Canadian Web site owner is not required to collect the GST/HST on the fee, as the supply to the non-resident is an advertising service that is zero-rated under section 8 of Part V of Schedule VI.