Ian,Thanks for linking to those videos; both are great! Footage is pretty good too. So now I'm a bit torn, and might choose the GP just because I'd be able to take it scuba diving as well - I currently use an iPod Nano 4 (the #5 didn;t have a video camera) in a generic underwater housing.
from what I understand, having a flat front lens makes for better underwater filming correct? I think that was one of the complaints about the older Gopros'. The new Hero 3 has a flat front type.
I posted a link to my snorkeling video but forgot I could embed it. Also if you look thru some of my videos I have one out side mounted on my GT-R at a track day at MSR and another one with my friends daughter doing back flips at a trampoline park.