They are basically the same parades but with Christmas decorations added to the floats to make them special for this time of year. I didn't get a chance to see the MGM one, but I've seen the photos. The AK parade was well-done imo. Some different music, but its all the same floats, with some additions to some of the floats that are more or less pulled behind the usual float (Donald's float comes to mind). All of the floats for both parades are nicely decorated though so they do have a distinct Holiday feeling than the ordinary day-time parades have.