Mad Hatter was on the cruise last week (Magic, March 18-25). He appeared in the Atrium one evening after dinner (around 9:30 pm) - I think it was the 5th night - yes, definitely the 5th night because I remember we were in Lumiere's which opens into the Atrium and the Queen of Hearts came "storming" through the dining room.
A bunch of the Alice characters (Alice, Queen of Hearts, Mad Hatter and the Rabbit) were out in the lobby atrium when we came out from dinner. They had games set up (croquet) and were playing it with kids. Very short lines to see them as many kids had already gone to bed I guess. The Hatter was excellent.