I see "political correctness" as nitpicky overreactions. My sense is that some people need to live and let live, and not overreact when something just isn't the way they want to hear it. There are always going to be people you run into that you don't like/don't agree with.
Kobuk, I'm with you on the whole "Merry Christmas" thing. I was raised that way, and I will say it that way too. Again, if people can simply recognize that people are different, and not everyone is going to agree or like the same things you do, this whole workup over something as simple as a holiday greeting would be a non-issue. Some people make it a problem. I don't get mad if a store clerk tells me "Happy Holidays". Its one thing in a sea of "political correctness" that people wade through daily. Frustrating, but I try to not let it bother me.