:lol:
To sum up the info on that site, Gay Days are based around the first Saturday in June. There are "official days" for each park, which were mentioned earlier in this thread.
There isn't really a set period of time that people go for. Many people only go for the weekend, or perhaps make it a long weekend. Others plan a week-long vacation, but even then the arrival date varies depending on preferences and work schedules. (For example, my roommate and I are going down Thursday-to-Thursday, skipping AK's official day on our arrival day, and not going to AK until Monday)
Also, not everyone follows the "official" calendar other than Saturday at the Magic Kingdom. Just about everyone goes to that.
(It's kind of like the "MouseFest" gathering of Disney fan sites, forums and newsgroups in December. Most people go to the MegaMouseMeet on Saturday, but then pick and choose what they want to do of the other scheduled events).
So you can expect crowd size to ebb and flow a bit that weekend, coming to a peak on Saturday.
If you're in the official parks on Friday (Studios) and Saturday (Magic Kingdom), you can expect crowds to thin out a bit as it gets toward the evening, as there are some private-event parties at Typhoon Lagoon (Fri) and the Studios (Sat) those evenings.
Of course, those parties aren't everyone's cup of tea (or within their budget for the high-priced tickets).
And lastly, as a funny story related to the red shirts mentioned above...
The only time I've been down there for Gay Days, I was entering the Magic Kingdom to meet up with some friends. In front of me was your typical Mom, Dad & baby in a stroller. Dad was quite handsome, and happened to be wearing a red shirt. The two guys walking behind me quietly vocalized to each other exactly what I was thinking: "He is going to get hit on SOOO much today..." :lol:
-Rob
P.S. - Oh, and as a tip... If you're in the area that Saturday and want to see a VERY large firework display, around midnight try to be somewhere where you can see the sky over the Studios... Whether it's the Boardwalk, Yacht & Beach, or I don't know how far down the pathway to the Studios you'd be able to get...