There isn't a huge difference in cultures, broadly speaking. You won't find much that'll surprise you up here, except maybe the far superior beer. :) There are a few things that form the foundation of Canadian society that will explain a lot, however:

• I have a pet theory. The U.S. was born from armed revolution. Canada was born from a bunch of bureaucrats getting together and signing a document. The gun culture you have in the States does not exist up here, because we've never had to fight for independence (although we did defend ourselves from American invasion in 1812 - dig dig dig ;))
• Canadians do have a problem with national identity. We don't have rampant patriotism and in fact suffer from a bit of apathy in that department as a whole. On the same note, we don't assimilate cultures, expecting immigrants to discard their cultures in favour of Canadian homogeny; rather, Canada is all about multiculturalism, and even has a government Ministry devoted to supporting it.
• There's a distinct schism that runs throughout the country that is partly due to the population imbalance regionally and partly due to the Anglophone-Francophone dichotomy. To Westerners (which includes me and pretty much anyone west of Ontario) the East is Evil. When there's a Federal election, whoever wins the seats in Ontario and Quebec wins the country. Also, many Westerners would only be too pleased to see Quebec secede, because in our view, all they (as in Quebec's politicians -- not all Quebecers are like this) do is take money from the Western provinces and whine about how they're a "distinct society" and that the need to be "protected." Quebec in the eyes of the West is at the apex of arrogance. I'm told by American friends Quebec to Canada is like either California or Texas is to the U.S. - I have no idea if this is true.

I'm not sure how the latest incarnation of Canada's Immigration Act impacts work visas, but if you want to move to Canada permanently, you'll find that the new Act is severely boned.

Best of luck on your move up here. Despite all of our problems, it can be a fun place to be.