This one is from a Harvard student. The paper starts off saying it will not tie technology to flash mobs, so hopefully this will give some new insight.
Reframing Public Space Through Digital Mobilization: Flash Mobs and the Futility(?) of
Contemporary Urban Youth Culture
http://isites.harvard.edu/fs/docs/icb.topic497840.files/Molnar_Reframing-Public-Space.pdf