It will be very cold at that time, the average temperature may be about -24~-13C. Under such a low temperature, the batteries will be influenced much. You'd better use mechanism camera. If you want to use digital camera, better take measure to keep it with a normal temperature, eg, put it into your inner pocket of your overcoat.

Im there on 1st Jan 2006. That is the coldest of the 40 years history. Tour guide told us this happen in 40 years back. When we are there is very very cold (normal is -20C to 31C. But it turn out -40C. You better take mechanism camera. Bring along hot pack for camera. My digital camera spoiled. Luckily I put on double layer of long john, follow by sweater and winter coat. A plastic clove, follow by leather clove. Double socks and waterproof shoe or a special shoe wit nail (esp for ice) you can buy this type of shoe over there. (RMB80). Bring along a empty bottle for liquor use. You can buy liquor in Harbin. Remember! Don't bring in liquor. Custom won't allow. I leaving to Hokkaido-Japan soon.