Put it this way. Breaking through powder on the way in, if you didn't have snowshoes you'd sink up to your thigh every other step. On the way back, once the track had time to set up, I managed to walk the whole way back in my boots and didn't sink once.
Of course everything depends on the amount of snowfall, but based on last year, if we're breaking trail: snowshoes are a must. If we're only following a well established snowshoe/snowmobile track, maybe you could get away with boots until we start setting up camp, when snowshoes will be necessary to move around for the first few hours at least. Play it safe.. wintercamping in the bush requires snowshoes. Remember, we might get more snow while we're there and we'd hate to have to come back for you (or what's left) in the spring.