The lens is the 0.67 wide angle lens. It makes the HD video more 'GoPro like,' though not as wide as the GoPro fisheye lens (roughly 120 degrees while the GoPro is about 170 degrees field of view). That causes the video to appear smoother and more stable plus more light and more things to see at once. I also have a full-on 180 degree fisheye lens but am having difficulty adapting it to the #16 cam or my #11 cam.
can see more on how to do this on Youtube, plus comparison of the image (not my video, some other guy):
I am very happy with the #16 cam, which came on the market this past winter. Much better image and light handling than the #11 cam. On sunny days it is just a notch below my GoPro960. Nice to keep the weight/size down for my Skysurfer (but still run a Gopro on my flying wing) and $45 is easier to handle losing than a $200-350 GoPro!