Crested Butte is amazing and probably my most favorite ski area in Colorado. It is also rockier than fuck. Arapahoe Basin is a distant second in that regard. December is an awfully early time of year to be gambling on Crested Butte. Great town, great mountain though.
Best conditions are probably going to be Wolf Creek and I am getting a gut feeling California may pour it on early this year. Seems like Cali is due for a good early season. Though often it comes in mid November last until mid December when it does.