Christmas and the New Year are actually two holidays, so there is a plural, which in the English language necessitates the use of the letter "S." Now, I suppose you could say "Merry Christmas and a Happy New Year" but you probably have sh*t to do.
Jon StewartCritics have noted Schwarzenegger's only previous government experience was serving under President Bush senior as Chairman of the Council of Physical Fitness, a largely symbolic office, where Schwarzenegger's only responsibility was doing hundreds of jumping jacks he was going to do anyway.
Jon Stewart