From the video description:
"We snuck out into the middle of Broad Street to snap a pic in front of City Hall and all the crowds. When Will raised his hands for the picture, cheers erupted. So he continued to repeat the gesture, getting wild response from the crowd on both sides of the street up and down the street as far as we could see. We couldn't have planned this if we practised and practised. I wish the video was longer."
I love it!