Kev has blogged about this before, but I thought I'd chip in some more comments with my feelings on the subject.
Have you ever met anyone who was offended by the words, "Merry Christmas?" I haven't and I don't think I'll ever be offended by that line. I'm not an atheist or a churchgoer, but I honestly don't know how I could be offended by such a remark. Apparently some people are, but I question if these people are really offended.
A line like "Merry Christmas" is as harmless as "Have a nice day." Of course there is no guarantee as to how large or small the merriness or niceness one's experience will be, but the sayings are often meant in the most kindest of ways. Granted, "have a nice day" has no words relating to a messiah, but "nice" and "merry" are friendly bedfellows.
I say "Merry Christmas" in a way that owes no implication of a certain religious denomination because wishes of happiness know no boundary of creed or belief. While there are others that want to be picky about the "Christ" part being in there and not being in there, I want to keep saying it, possible offense taken be damned.
A TV news story I saw earlier this year featured a great line about our modern culture: "the land of the free has become the land of easily offended." I think this line fits perfectly in this case. The thought of homogenizing everything with "Happy Holidays" is silly to me. If people want to be sensitive to the those that get offended by the inclusion of "Christ," well what about all the grinches and Scrooges who hate all things Christmas, Chanukah, Kwanza and Festivus? Are we not far off from appeasing those people too? (Reminder: those people are really hard to please and probably don't enjoy pleasure even if it's addressed)
Maybe this kind of coverage is exactly what anti-Merry Christmas activists want: people talking. Well, consider yourself victorious in getting people talking, but we're talking about how lame such ideas are. Isn't this supposed to be the most wonderful time of the year?