I forgot about the USB plug. For flight testing we wanted not only to power the camera but also record headset audio and display a realtime video preview to the engineer in the back seat. Doing all these things simultaneously required us to us the high-density connector.
With the new GoPro HD Hero2 cameras, you can do this all without touching that high density connector. In the version released in the past year, the camera has audio input as well as video output (HDMI and composite) during record. Nice upgrade from the original version.
helicopterflyer: the GoPro cameras can be programmed to start recording as soon as they're powered on, no need to manually trigger.