I think it is reasonable to say 'Merry Christmas' because, well, it *is* Christmas. But it would also be reasonable to wish people 'Happy Eid' or 'Happy Hannukkah' for the same reasons. I don't like the idea of mashing all the holidays into one, and I think that people (certainly the non-Christians I know) appreciate it more when you make the effort to wish them Happy *insert whichever festival* when they know you don't celebrate it yourself.
I don't think it is politically correct, but I think it wrong to suggest that non-Christians would object to be wished Happy Christmas, when clearly it is just being friendly and polite. However, it is equally wrong to assume that any who says 'Happy Holidays' instead is being anything other than friendly and polite, so carry on!!!
It is 'so American'. But..well....you are American, what the hell does she expect!!!
![Grin ;D](https://www.talk.uk-yankee.com/Smileys/classic/grin.gif)
Vicky