I seem to recall (from a year or two ago) that there is, or will be, a "Lightning Bolt" version of this. It is optical using fiber-optics in the cable rather than copper wire. Pictures of it were showing it as part of the USB-3 port rather than minidisplay-port and the optic cables were in 2 corners of the connector (the light transmitters/receivers were built in the devices and coupled to the fiber). They indicated that the optical version would run much faster than the wire version, didn't require active electronics in the cables ($$$), and could be available some time after the Thunderbolt was released.
I haven't seen much about it since ... so perhaps it is still being engineered to work?