The idea that "Merry Christmas" is hate speech is fairly new, to me and Tom Flynn's reference in this OP-ED to "War on Christmas," Year 2, suggests that there never was a war on Christmas until Bill O'Reilly and John Gibson talked about it in 2005, but if you scroll down to the bottom, you'll find that Flynn has been fighting The War Against Christmas himself since at least 1993, when he published The Trouble With Christmas
As some Americans' holiday season draws nigh, secular humanists, Christians, and non-Christian believers should all reflect on what will make this season different from any before it. Depending on context, wishing someone "Merry Christmas!" can now function as hate speech. In Religious Right Wonderland, you don't wish "Merry Christmas" any more; you wield it.OP-ED The New Hate Speech By Tom Flynn
You can wish the Council For Secular Humanism the compliments of the season here.