Should Atheists Celebrate Christmas?

(Here's part of an email I just sent out to our Chemists for Christ group.  We're studying the book of John right now):

John may not have put the Christmas story into his book, but Luke sure did!  Linus quotes it as he explains the meaning of Christmas to Charlie Brown. 
Not that everyone would agree Linus' conclusions.  Evidently one topic of discussion among atheists today is...

Should atheists celebrate Christmas?
In case someone you know is wrestling with this question, here's some pros and cons (I did not come up with these; I am only summarizing what an atheist wrote!):
Cons
It may make Christianity seem more popular than it really is
It may bolster evangelicals' claims that America is a Christian nation
Christmas' pagan roots aren't any more of a connection point than its Christian ones: atheists aren't pagans any more than they're Christians
Telling your child that Santa Claus exists may precondition them to believing in Christianity's myths ("is this worth the risk?")
It could make you or your children feel ostracized ("Being different isn't easy, but who wants to be a hypocrite just to fit in?")

Pros
Atheists can effect changes in Christmas that Christians hate

But, of course, the most important question is, "Should atheists celebrate any holidays?" 
("So-called 'alternative' holidays won't make much progress because in the end, it's clear that they aren't any more "rational" than Christmas."  "Once the question about celebrating Christmas is introduced, the next logical step is to wonder whether atheists should be celebrating many or any of the holidays traditionally observed. Tom Flynn, for example, argues that "a humane holiday should be global and universal, equally relevant to all humans, regardless of their cultural heritage or where they live." Leaving aside problems like separating holidays from the rhythm of our experience of time, this is worth thinking about.")

I have to admit that until tonight I'd never considered the momentous question this would be -- to celebrate, or not to celebrate?  Many years ago G.K. Chesterton wrote about why Christianity inspires holidays while secular humanism does not: "There has been no rationalist festival, no rationalist ecstasy.  Men are still in black for the death of God.  When Christianity was heavily bombarded in the last century upon no point was it more persistently and brilliantly attached than upon that of its alleged enmity to human joy.  Shelley and Swinburne and all their armies have passed again and again over the ground, but they have not altered it.  They have not set up a single new trophy or ensign for the world's merriment to rally to.  They have not given a name or a new occasion of gaiety.  Mr. Swinburne does not hang up his stocking on the eve of Victor Hugo.  Mr. William Archer does not sing carols descriptive of the infancy of Ibsen outside people's doors in the snow.  In the round of our rational and mournful year one festival remains out of all those ancient gaieties that once covered the whole earth.  Christmas remains to remind us of those ages, whether Pagan or Christan, when the many acted poetry instead of the few writing it...
    "The strange truth about the matter is told in the very word 'holiday.' ...  It is hard to see at first why so human a thing as leisure and larkiness should always have a religious origin.  Rationally there appears no reason why we should not sing and give each other presents in honor anything -- the birth of Michael Angelo or the opening of Euston Station.  But it does not work.  As a fact, men only become greedily and gloriously material about something spiritualistic.  Take away the Nicene Creed and similar things, and you do some strange wrong to the seller of sausages.  Take away the strange beauty of the saints, and what has remained to us is the far stranger ugliness of Wadsworth.  Take away the supernatural, and what remains is the unnatural."  (From the book Heretics, originally published in 1905; this edition published in 2000, pp. 48-49).

Praise be to God, the source of every good thing!