These cameras are amazing! I have two and you can look through the WakeWorld Vimeo page
to see a ton of stuff that Kaesen has shot with it. I have yet to see a camera come close to the GoPro in picture quality and, most importantly, smoothness. What convinced me was seeing dirt bike helmet cam footage. I know how bumpy that can be, but you would never know it from the footage. I just wish I was better at editing so that I could use more of the footage I've shot.
I use a simple shoe string as a tether. Unfortunately, the case doesn't have a loop or anything on which you can tie something, but you can squeeze it through in the area where the mount is. Also, they just came out with some pretty cool new features. One, which I just bought, is a screen that attaches to the back so that you can see what you're shooting and review shots. It comes with a case that encloses everything. They are also coming out with a 3D version, which looks like two cameras in one housing. I saw these in use at Supercross on Saturday as they were filming the crowd with a big LED ring light all mounted on what looked like a set of handlebars.