Talking about accents, I was watching a CBC documentary a few years ago that talked about this very thing. The general difference in Canadian speech is inflection. That is, Canadian inflection and general speech patterns are far more "musical". Of course, we're probably comparing to West Coast USA here. The program also talked about changing pronunciations and lexicon coming out of NE States.

After watching, I've become a lot more aware of my speech patterns when presenting to Americans.