Not a great idea in practice. Over Chinese New Year (the Chinese call it "Spring Festival"), the whole nation people grinds to a halt. There will be a handful of public events, but really it's a family festival where people stay at home with their folks. The worst part is getting around - imagine millions of people all trying to get home for the big day. However, despite a large number of museums and attractions being closed and a pervasive "can't be bothered" attitude, it is a good time to visit the Great Wall, Forbidden City, Summer Palace etc. They won't have the usual crowds, and you'll get much better pictures. Assuming, that is, frostbite doesn't get you first - expect temperatures to stay below freezing.
Philip Sen