I was in HK for New Year's Eve 12/31/04 and it was very cold. We stayed at the Sheraton that evening and it seemed like there were millions of people filing down Nathan Rd either to cross over to HK island or to the countdown in front of the Penninsula Hotel. They closed off a lot of the streets right down by the Pen and the Sheraton, so we didn't leave the hotel. But there is a countdown at the Times Square Mall in Causeway Bay.

As for the transportation, we just "bought" for 50HKD an octopus card that we used for almost a week, and we just added money to it when we were low. And when we left HK we gave back the cards at the station at the airport and we got the 50HKD back plus the balance on the cards. It was quite affordable, and you can use the octopus card to buy things at stores too. I think you also get a discount for all public transportation.