A December event that lasts one or two days nerfs everyone with a life, friends, family, anything and everyone - except for the small group of uber-MMORPG AO obsessed fanatics.
Don't nerf Christmas - make the santa leets and bronto reindeer hu8nting take the rest of the month of Decmber. Give everyone a chance to get in on the fun.
FC is like the bartender and Ao is like beer. Serve Hapopy Hour all December long - dont just have free beer on Christmas day for the drunks who live upstairs of the bar.