I got my surveys in, yay!
Most people have not seen a flash mob.
The majority thinks they should be in a store or mall.
The majority are stuck between a battle or a dance.
A huge majority (my results were more than 3/4ths!) would participate.
The demographic was teenage students.
I have not formally read the open-eneded, but people were either all for it, or thought they were "stupid."
People also mentioned singing and dancing, especially dancing, often, suggesting this is the 'stereotype': A synchronized dance in a mall/store.