Though Christianity is not a popular religion,
Japanese people (including myself) celebrate this holiday.
In America, I believe Christmas is more of a family holiday.
In Japan, it's more of a romantic holiday which you may spend with your friends or significant others. (this is the case for the young generation)
Due to the popularity of this holiday, businesses go above and beyond in decorating the city with illuminations! The illuminations I've seen in Tokyo are much more intense than the ones I've seen in San Francisco, Boston and NYC. Additionally, the illumination themes change every year; so you'll see a new design every year.
Check out the list below for the illuminations I want to visit for the year 2015!