There are a bunch of radio-control vehicle guys who are happy with the GoPro Hero HD for "first person" driving. This includes helicopters, planes and trucks. That's nothing new, here's another thread on it: gopro-on-a-helicopter-t173.html
Currently, the only way to get live video out to our video transmitter units is to stick a cable into the SIDE of the GoPro for the TV or RGB signals, and also to trick the 2010-January firmware into a live video mode by giving +5V to the usb-mini-b jack on the SIDE of the GoPro. Well, cables on the side are not particularly handy, especially if you're trying to use the clear shock casing.
The GoPro has a 30-pin bus connector on the back which will be the foundation for a few promised accessories like a second battery, and a mini LCD screen. I noticed that the connector looked familiar: the same connector is used for the MyVu Crystal goggles, and several generations of iPod music player docks. DO NOT CONNECT iPOD DOCK ACCESSORIES OR OTHER PRODUCTS INTO YOUR GOPRO BUS CONNECTOR.
The power pins are different and you will likely cause damage to one or both devices.
Okay, now that I've given the big disclaimer, I want to say that I did find this handy little gadget, and am using it to reverse-engineer some of the GoPro bus connector functions. < iPod Gizmo connector breakout board
I have determined the +5V and GND pins for the GoPro, can turn on the GoPro through the bus, and can do the "live video" trick without touching the USB mini-b plug. I have not yet found out how to get live composite video or audio out of the bus, but I may discover this with a little more research. My goal is to get all the features of the side connector out through the back, so I don't have to cut the clear plastic shock casing.
Rambo, before I just go ahead and list the pinouts I've found, I wanted to find out if there's any problem with that. It's 100% legal to reverse engineer a product like this at my own risk, and even to publish my findings, but I don't want to put any other agreements you may have with GoPro at risk.