It's the 9th of January. It's typically thought to be bad luck to have them up longer than 12 days after Christmas, which means the 6th of January.
I think DannyTheNinja's suggestion is the best. Have it for one day like google. Except, don't have a custom logo for such a wide selection of events. Maybe, Christmas and Easter? Also, what about the days walking upto Christmas? Can we have it change each day! Like a google
doodle? 
that would be cool.
Also, can the "Happy New Steer" be taking down now. You don't hear anyone mention happy new year anymore really. And it's getting slightly old.