Yeah they're pretty much standard issue on cars sold here. Generally I don't plug in my car inside the garage unless it's going below minus 30 C or so and then it is on a timer so it's only on for about two hours before I go to work. Just enough to heat up the oil so it starts more easily. I do plug in my car at work because it is parked outside all day. In one of my older cars I used to have an internal car heater as well, but haven't bothered with this car. Usually switch to 5W30 for winter as well, though they've got a 0W30 out now that might be interesting.
The magic block heater line occurs somewhere around Fargo. You'll see the plugs hanging out of every car in Grand Forks (70 miles north of Fargo; 130 miles south of Winnipeg) and on most cars in Fargo. As you go west towards Minneapolis they become a lot less common (it seems). Maybe one of the MN guys can confirm whether there are many/any in that burg, but I don't think so.
It is definitely consistently cold enough to merit them as well. When we get snow (some time between October 15 and November 15 is the norm for it to arrive and stay) it sticks around for 5 months or so. During that time period the average monthly temperatures for Winnipeg are as follows:
November -5 C (23F)
December - 13 C (8.5F)
January -16 C (3.2F)
February - 13 C (8.5F)
March -6 C (21F)
(0 C = 32 F)
So well below freezing. Not Alaska cold but pretty damn cold no matter how you cut it. Generally it's about 10 F colder, on average, than Minneapolis in each month during the winter. This past December was quite a bit colder than normal, at -19.3 C (-2.7F) and January thus far is quite cold too. In a sense you definitely get used to it, but it's still frigging cold.