re: "Merry Christmas" vs "Happy Holidays, etal", Serenity puts it all in perspective.
A taste:
So I have a plan. From now on, you all wear your religion and anything else about you on a sign around your neck, allow me the time to read it as I pass you on the street so that I know what the hell I can say to you and what I can’t say to you without you pissing and crying about it.
