I'm new to these boards, but we just got back from a three day trip. We spent Monday at Animal Kingdom, Tuesday at Hollywood Studios, and Wednesday at Magic Kingdom. We had a fantastic trip and loved the cooler weather. However, it was more crowded than we were expecting. My group has been before in August and May, and both of those trips seemed less crowded. We did everything we wanted though with fast pass and getting to the park early. I will say our Animal Kingdom day seemed the most crowded. It had rained all day the day before, and it was also an early morning hour, so we figured this contributed to the crowds. Anyway, yes January is crowded, but we'd do it again. We would rather have the crowds than the August heat.