I'd be happy to give my $.02! After all Kerry... he did say EXPERT advice...
The major issue with having someone who is still learning to skydive (that can mean on student status, that could mean has 400 skydives but only makes 40 a year, etc. if you get my drift...) wearing a camera is that it adds a multitude of complications to the jump. It doesn't mean on every jump it will complicate things, or that it will ever complicate any of your jumps, it just means the potential is there.
Snag points... The way the camera is assembled on the helmet shown in the link you posted is on the side of the helmet. If you were to see a slow motion video of your canopy opening - you would see that the risers pass right past the sides of your head as they transition from behind you (on/in the rig itself) to either side of your head with your canopy open and flying straight (or at least we hope). The camera on the side of this helmet adds the potential for the risers connecting the lines of your parachute to your rig to hit it and knock it off, hit it and slide past, or hit it and get stuck. My one and only cutaway Johnny is from an entanglement from my left riser and my camera and bracket. I'll tell you about it next time you are at the DZ. I had 216 jumps. It freaked me out a little

I never saw that helmet again! It's very easy to say "no biggy, it gets entangled, I get rid of it...". And, in some cases, it might be that easy. But I can tell you from experience, I had to react very fast and keep my cool to take care of my issue. It left me under my reserve below 2K which got my blood pumping. As a student, these reflexes are something you are still learning. Skydiving isn't one of the things in life you really want to "learn the hard way" if you know what I mean.
Other then snag points you do have the fact that a lot of people tend to lose focus on the rest of the skydive because they are taking the time to think about the video. Now - for the purpose you are thinking of - I don't think you would have this problem. But for future reference....
Kerry - I think that wearing your helmet without the camera on some skydives is a good idea. Heck, make sure your risers clear your set up okay before you put hundreds of dollars on there to take a spanking! I tell you what Fletch once told me when I was starting to do video. I wore my camera on a skydive, but didn't turn it on. It's a waste. You can ware it, and have it on, and not be distracted by it... or at least no more distracted by it then when it's on your head and off. By all means, if this is a step that will help you to feel comfortable please do take it - but it ended up being a silly step for me. If I didn't need/want to shoot video, I didn't wear my helmet because it eliminated that risk from that skydive...
Now I have seen little camera's that look like they are the size of a crayon on the side of helmets which aren't that bad. One issue you get with a new jumper trying to catch video that way is they open up and they do something cute/silly/entertaining like throwing peace signs in front of the camera or whatever. Then by the time they are done geeking their new camera, they realize they are faced away from the DZ and might not make it back or that they have a tension knot or something else that they really could have taken care of 30 seconds earlier and been better off. Again, I don't think you Johnny would have this issue, but it is something to think about.
As far as cameras and set ups go - the go pro seems like a great move in the right direction. The size alone is great. I'm pretty sure they could mount that puppy on the front of the helmet and do a lot in the way of reducing the possibility of a snag.
What is it that you are wanting to get video of Johnny? Want me to chase some of your skydives? I was lucky enough to have this really hot dude follow me on my first 100 or so skydives... I'm indebted to the student community... I'd gladly take some pictures and video for you next time you are out
