Take this with a grain of salt because I'm not all that familiar with the NEC:
My understanding is that, for the most part, the NEC and CEC have been harmonized on standard trace practices like conduit fill, ampacities of wire, service entrance, outlet spacing, etc so we work pretty much like you do.
As for the different voltages, I believe that most of that is due to regional history. For example, in the relatively new western provinces our single phase voltage is typically 120/240 and the 3 phase is 120/208 for commercial and high density residential, 277/480 for large lighting loads, or 346/600 for heavy commercial and industrial. Out east in the older provinces where the manufacturing history is more entwined with the US there is much less of the 600V stuff because 480V is what they grew up on.
Beyond the basics, some of the other things I can think of are that we don't have to use TR receptacles (yet), there are special consideration for services in northern areas to avoid condensation, and UV stable pigments in exposed wire insulation is a must. Oh, and nobody really cares if an outlet is ground up or ground down.:wink:
Just out of curiosity, how do you define a sideways service?