I'm an atheist author and an activist for secular governance in the U.S. and elsewhere, and I celebrate Christmas every year.
It's not all that unusual, actually. Contrary to what you might believe if you've been fed a steady diet of right wing propaganda over the last few decades, atheists don't spend the holiday season eagerly waiting for someone to wish them a "Merry Christmas!" so that they can pounce on them, insult their faith or file a lawsuit. In other words, there is no "war on Christmas." And if there is such a battle, atheists are not leading the charge.
