The whole "Secular Humanists are trying to destroy Christmas by insisting that people say "Happy Holidays"" thing is really driving my crazy, for several reasons.
I think that what bothers me most is that, let's face it, Christmas is observed by more secular humanists than any other holiday. I don't know anyone that is not Jewish that celebrates Hanukkah, or any non-Muslims that fast for Ramadan. I don't know anyone at all that celebrates Kwanzaa.
But I know tons of non-religious, even atheistic people that celebrate Christmas. I am about the most secular humanist that you will ever find, and while I don't have a tree or a nativity scene around, I have Christmas presents. For me Christmas has very little to do with the seizure of a pagan festival for Catholic recruiting (it's traditional meaning), and everything to do with separating the people I know into those who are worthy of a present,and those who are not. Really, isn't that the true reason for the season?
Personally, I started consciously saying "Happy Holidays" instead of "Merry Christmas" at least ten years ago. The reason, surprisingly, wasn't because I wanted to destroy the (apparently very, very fragile) foundations of modern Christianity. It was because what I was trying to communicate with this well wishing was not about me - it was about the person I was wishing well to. While I might be celebrating Christmas, when I wished well to someone, I had no idea what holiday they might be celebrating, and it seemed a bit, well, dickish to assume that I could impose my holiday on them. So I started saying "Happy Holidays". Because it's not about what I want - it's about what I am wishing for them.
And that, I think, is what people like Bill O'Reilly will never get - that, for a moment, it is not about them.