I thought it was the NYS Regent's week, which will be week 3 in 2013.
Just fyi, in the way of an update, according to the beach attendants things at the SC at least wee markedly different this year, without any issues or incidents and, supposedly the only difference from any other week is that there were a lot of people, akin to one of the other holiday weeks.
I had heard that Marriott officials had intervened last year, so hopefully this is a positive trend that will continue.