Stronger USD does help, though exactly how much I'll leave someone from the U.S. who has made the trip to comment on here.

Very similar culturally. Our proximity to the U.S. has had a massive impact on our culture (what exactly constitutes distinct 'Canadian culture' is a bit of a fraught question, even if you just stop at 'Canadian settler culture'. But, beyond leaving this provactive song, I digress.). But lots of regional differences - your experience in Antigonish, NS will be different than Toronto, ON, which is different from Trois-Riviere, QC; Brandon, MB; Saskatoon, SK (lol, jk, no one goes to Saskatoon), etc. Then there's the North, which is very different from anywhere in Southern Canada.

There's an impression that we are more polite, in aggregate, than the U.S. I don't know how true that is and believe it's a function of population difference (U.S. has way more people, so if the % of assholes is the same that's still a whole lot more assholes), but whatever.

If someone from the U.S. comes here and isn't a knob, they'll generally be treated fine (though perhaps the usual jokey jabs have a little more spike to them these days, given the state of U.S-Canada relations). They usually marvel at the little differences (bagged milk gang what-what).