I found a program called Mobile Presenter Pro which is supposed to share your screen to multiple iPads. However it receives less then stellar reviews as it is slow and pretty much just a VNC. I hope there is a solution for my client to present on 1 iPad and share his screen to multiple iPads in the room by Bluetooth or Wifi. Depending on the Wifi of the locale they are presenting is tricky as they normally don't have this information at hand. Ideally they would just walk in with their iPads, hand out the machines which share the screen but can't edit/change the presentation and deliver the presentation from their master iPad.