I prefer mitts to gloves. Wouldn't be able to change a tube in them, but probably wouldn't do that anyway. I have a 6 mile commute and can push the bike home if needed.

Mitts are much more adaptable as the temperatures get colder. You can have better liners or even put another pair of mitts over the first one with liners. All your fingers and your thumb if you need to, can be in one ball in the mitt to warm up. There is less surface area to the mitts, so less heat loss.