GoPro as a company has been pretty impressive. At first I discounted them for motorcycle applications because they looked awkward and cheap. Reality is their system is the most versitile with respect to mounting options and image capture. The first cameras had flaws, they worked on them, then launched the HD which addressed most of the issues and added a narrower field of view which works well on race tracks with fixed vehicle mounts. For $259/$299 it's a pretty hard package to argue. The bac-pac at $79 and spare batteries at $19 are a deal.
I was just at Fontana testing bikes and since we were swapping bikes all day I couldn't fix mount to the bike and went with the helmet mount like this:
The audio wasn't good (at all) as I was running the closed back due to speeds over 160 and the helmet location is in very "dirty" air, but the video capture turned out pretty good:
I can't wait to get my car our this summer and play with it.
If you're thinking about one, you won't regrete the purchase. I set my friends KTM shop up as a dealer and our customer satisfaction has been great. Bikes, skiing, fishing, scuba, swimming pools, water parks, skydiving, dog-cams you name it. The still photo perspectives you can capture are also very impressive.