I read this link, but I do not know if things have changed .http://www.canadavisa.com/canada-immigration-discussion-board/-t10214.0.html
When your application for PR is approved and you are already in Canada, what is the landing procedure, is it going to US border, or is it just going to the local immigration office?
Btw Make sure not to pass to USA if you dont have a visa.. other wise they will stamp "Rejected" on your passport which is not good if you want to apply for any future US Visas... Just go out of the canadian boarders walking and reenter.