Scratch, were you considering upgrading to the main building concierge or sugar loaf? Also, would you be spending most of the day at the resort? If you answered main building and yes, then I'd have to say, that it would probably be worth it.
Yes, you would have to pack up your other room a little bit early, but as it's for only one night, you could live out of a day bag. The Disney resorts will take care of moving your luggage between the 2 places. Even if your new room is not ready, you still have that beautiful lounge to relax in. The decorations are beautiful and you'll be overlooking that great tree and in the evening, the orchestra will be playing on the floor below yours. If you did want to get a little crazy and go into the MK on Christmas, then you're only one monorail stop away.
Even if you aren't staying in concierge for your full stay, I've heard of many instances where they will still make all of your priority seating arrangements for you and anything else that you need. That's a nice perk, considering the time of year that you are going.
Tammi