It's a great idea as long as it is not overused in everyday life.
GET OUT OF MY WAY!
It's fun to watch people's reaction.
I like the idea of creating events which shakes people out of their normal everyday routine and way of thinking, but many flash mobs fails to do so. They become brain-dead useless youtube entertainment and the purpose of most of them is solely simple plain entertainment. In such cases I think that the individuals, organizing the flash mobs, as well as the participants, could use the time and energy to solve much more serious, relevant and important issues problems. This goes for the entertainment industry in general.
seen to many, its not relevant any more in my opninion :)
yes, it is very interesting and creative, it is an effective and artistic way to have people's attention to some causes :)