Sutty - You have better eyesight that me, as I cannot determine one way or another whether they are wearing fall arrest equipment or similar. Have you seen additional images from other angles, are are you assuming from this single snap? I would be very surprised if they weren't secured by some covert device which are quite common in the theatre game

Frontal view.... http://www.google.co.uk/...;ved=1t:429,r:0,s:0,i:72

If you zoom in you can see they are wearing harnesses

Those of us who watched on TV the grand displays preceding the formal opening of the Olympic Games in late July will probably recall people being lifted into the air on platforms, especially a mega-sized NHS bedstead. There was little scope for discussion then because it was very evident to viewers, with the help of TV cameras zooming in to give close-up views, that harnesses were in use. Also, the associated network of cables spanning the Olympic stadium was described as having a capacity of 25 tonnes, considerably more than whatever it was required to lift/support at any one time. Illusion can be a very effective part of entertainment. It seems that the organisers of the display which prompted this thread were successful in this regard because the guys sat on the supended platform didn't SEEM to be wearing harnesses! However, photo zooming was able to probe through the illusion!