Also, don't forget to call the resort you are hopping to before you go. They sometimes advise you that they are too busy, but I doubt that will be an issue in January. Hopefully it will be warm enough!
If you are a member, staying on points at a DVC resort and pool hopping is not blacked out for the holiday period (could be two weeks at some holiday times), you may pool hop to any Disney owned pool on the property except for any BC/YC/BCV pool, BLT pool or AKL/AKV pools.
If you are not a member, you cannot pool hop. If you are member, but not staying on points, you cannot pool hop. If you are a member using points, but not staying at a DVC resort, you cannot pool hop.