Gay Days has been a tradition at Disney World since 1991. From Wikipedia:
Gay Days at Walt Disney World is a gay pride event held at Walt Disney World near Orlando, Florida the first week in June. Various circuit parties and dance events comprising the majority of the schedule, culminating in a park-sanctioned (but not park-organized) "Gay Day" at the end of the week, in which gay travelers wear red to let others know why they patronized the park that day.
Although one Christianist hate group flew "warnings" over the park (above) this year, I got a report from longtime DustBunny Tivo Mom - who happened to be at Disney World with her husband and young children this weekend - and it seems like everything went swimmingly. Tivo Mom writes:
"This weekend was Gay Days in Disneyworld. While we were there my son asked why so many of the men were dressed alike or all in red. My husband and I told him that this large group of people got together once a year to hang out and have parties and the red shirts let them know who was part of their group. My son and daughter proceeded to tell us that they "looked like a fun group of people because they seemed to all be smiling and they had cool rainbow Mickey ears." I thought that you would appreciate."