Digital cameras seem to work pretty well in cold weather, as they don't have the film transport issues that screwed up film cameras in the cold.
The biggest issue I have is condensation from coming into a warm room from the cold outside. Some paper towel to wipe off the condensation is a good thing to have, and make sure you don't change the lenses until your equipment is at room temperature to keep the condensation from getting inside your camera, would be my biggest pieces of advice.
David Buzzard