"where the scientist touches his iPhone like tablet to the computer screen and swipes a 3D image off the screen on to the tablet. He then walks across the room and swipes the image on to a window"
This would be EXTREMELY easy to implement if the whole "web-based OS" platform idea took off, where everyone's computers were simply localized data-chunking systems and your actually desktop is "out there." Then it's just a simple matter of dumping your desktop session to whatever device you desire. You can already do this with Citrix remote sessions or Virtualized Desktops, just not so seemlessly as in Avatar. With a 30mm range for the TransferJet, I don't see a huge need for complicated authentication. If they reduced the range some more and REQUIRED the device to be sitting on a landing pad of sorts, then it really should work just like a USB device IMHO.