Also, MK is always the busiest, followed by Epcot, MGM, and AK. Epcot is about twice the size of MK so you do not feel the crowds as much, but they're still definitely pretty busy. However, we spent Easter, which is one of the busiest WDW days of the year, at MGM and did not feel the crowds AT ALL. We even walked right on to Millionaire with no wait!