We have my wife's elder brother and sister here for a week, so we have started lighting the fires in the kitchen and the front room. With the doors open, the whole house keeps comfortable. Although we don't actually need them yet, there is no doubt that it makes the place cheerful and cozy.
The big decision will be when they go home. Do we keep the fires on or wait until it gets really cold? Its only around 13/15 degrees during the day at present. Usually, we just put another jumper on or start with the thermals before burning wood.
Maybe we'll just switch the blankets on at night.