Christmas is not an official holiday here. Everyone has to go to work, I still have class at 8:00AM (my listening comprehension teacher basically threatened to kill us all if we skipped for Christmas), but Chinese young people absolutely love Christmas. There's Christmas music playing in various places, giant inflatable Santa Clauses in many buildings, and Christmas trees. Today there are fancily wrapped apples for sale everywhere, because the Chinese word for Christmas Eve is 平安夜 (Ping'An Ye), and the word for apple is 苹果 (Pingguo) and since the two pings sound the same, everyone buys "平安果“ - Christmas Eve Apples.
Furthermore, the Chinese internet loves Christmas. Observe:

This is RenRen, China's answer to Facebook. I giggled a lot when I saw the Santa Hat imposed over my picture today. My 8 minutes ago status update you might notice there says that I wish everyone a happy Christmas Eve.

This is the homepage to Baidu, China's most popular website. It's basically Google (which is also popular here) but is far more kickass in that you can download pretty much every song ever.

Tudou is one of China's Youtube knock-offs - I personally much prefer Youku, but apparently Youku is uninterested that it's Christmas. Haha.

This is Zuosa, Chinese Twitter. I only use Zuosa because it let me link my account to my Twitter account, so while I still have no idea what anyone else is saying on Twitter, I can update mine. But, really... you can say a whole hell of a lot more in 140 Chinese characters than you can posting in English.

My tree!! And some of our cards. My roommate and I are well-loved, our TV top is full of cards too!! There are lights on this tree... not sure why they photographed so poorly!!

I also had no place to hang the other lights I got, so I just strung them around my headboard. I think it's festive!!
I'm not yet quite sure what Chinese people do on Christmas Day itself, as our teachers all kept saying "oh, only young people celebrate Christmas in China", but I'll be sure to let you all know!!