Pic related is basically where I live, somewhere in Canada.
I prefer the summer, maybe because it's so fleeting. I like being able to sit with the window open or go for a walk in shorts and a t-shirt in the middle of the night, and we only get couple months of this. Then it's the long dark and the deepfreeze again until May. Days in December are about eight hours long, and you can easily go to work in the dark and go back home in the dark, which becomes like cabin fever without even the benefit of seclusion. Snow blindness and glare from the sun coursing across the horizon is annoying and dangerous. At sunset, runoff from the snow mounds turns the sidewalks into sheets of ice. It's hard to mitigate the hazard of ice completely.
On the other hand, there's something satisfying about being fully tanked up: overcoat, hood, thick pants, scarf, gloves, and boots. It's like in a game when your armor class is so high you can just stand there and let the enemies hit you. Some nights it'll be a couple degrees below the freezing point, and the wind is calm, and it's snowing gently in big clumps that scatter the streetlight into a pervading, golden ambience. On a long outing I might notice that the wind has died down and pull my hood back because I'm actually too hot, and the air is crisp and refreshing. Some things are nice to look at, like a frozen lake. Miles of pure, perfectly level, untrammeled snow. Also, running through a field when there's a foot of snow on the ground is the best cardio there is.