Agree Oomuchi, it depends on the officer. The reason i say this is, another couple was being interviewed by another officer (next window) and he was pretty loud ..and sometimes a bit blunt. I guess they didnt have all the documents handy (especially COPR).
Ours was very cool, he was very casual, but made eye contact when he asked questions like "have you ever been a citizen of another country besides XYZ, have you been known by any other name? etc" ... Based on my experience, the interview was primarily to verify all the originals (against photocopies we submitted with our application)...My wife has about 3 pages of travel aka. travel calculator (mostly to US) and she didn't have entry/exit stamps for most of them. We took a copy of the I94 report from the website and provided that to the officer. He appreciated the gesture. He did randomly check for few stamps and thats about it. Btw, our status changed to "Decision made" this morning. Pretty fast I must say. And thia am, I see 3 new oath ceremonies in Kitchener on Jan 15 and 16. So I assume they will invite us on one of those days if we are lucky. Good luck!