VideoManiac -
We use Midland LXT310 radios with headsets that allow us to communicate without having to touch the "walkie-talkie" itself. It has a mode that will sense one of us talking and automatically send the voice, but we prefer to use the little button on the headset cable when talking. This button also makes the clicks we use during ceremonies. You have to be careful though to turn off a feature of the radio that will beep whenever a signal is being received (button pressed on other radio).
This month's Digital Video magazine has an ad on page 54 of the Eartec system mentioned above. It costs three times what our set cost with the only obvious advantage is not having to deal with two headsets.
As for the headset we use to monitor our cams' audio signals, I always worry one of us will forget we're "attached" to the camera and walk off, toppling a tripod with a $3m cam on top. I've already dropped one VX2100 and not looking forward to my second trip to the shop. Does anyone know of a decent wireless headset for monitoring audio?