I can post some 1080p footage taken from a car if you wish. This mode should be ok on a helmet mount.
[edit]
Here's some anyway. Bear in mind they are shot through a windscreen and glass reflection is a factor. Audio is removed to screen out the chat! Sunny late afternoon, if I remember correctly.
These were actually shot with a 1.16 beta. I haven't had much time to try out the 1.16 final but it seems to me that the developers may have softened it a little to reduce grain.
St Just
Sennen
Zennor
Penzance
Nanjizal - no windscreen!
John
Finally, some bike footage, handlebar mount, 720p at 30fps taken today with 1.16:
Debenham
All the above are 25mb downloads or thereabouts.
I'm not unhappy with the quality overall - I've used the ContourHD 720p, the 1080p version, some Flip-style HD cameras and several Chinese muvi clones, both sd and upscaled sd, as well as having access to Go Pro, HD bullet cam and the newer Chinese cheapo 720p units' footage. I think the GPS 1080p footage compares to an equivalently priced HD camcorder, although the 720p mode of the latter will probably be better.
Go up to, say, the mid range Panasonics that start at nearly twice the price and there will be a big jump in quality. You would be comparing chalk and cheese, though, and it's not just about the image sensor used - I wouldn't subject the complex lens of an expensive camcorder to the kind of road vibration that the Contour gets from a handlebar mount on a 50 mile ride.
They all have their pros and cons - how they cope with changing light conditions, quality in low light, mounts that can be plain ugly, high bit rates that require expensive high capacity cards and limit battery life, external battery pack use etc. etc. For example, the ContourHD 1080p has the same optics and image sensor as the GPS unit and (now) a slightly sharper picture - it is however much worse at coping with changing lighting conditions and handling bright skies and dark foregrounds.
The Contour+ looks promising but given all the problems they've had with its predecessor, I would hold fire for a while until some user experience can be assessed.
John