Pentax Optio W I am using Pentax Optio W series cameras (W30 recently). They are quite similar to Olympus Stylus SW line, but have better video capabilities (even in comparison to the newest Stylus SW 1030).
I have a GoPro 3 I took the camera on a trip to Belize last spring and took about 500 pictures and 30 min of video on a 2gb memory card and had memory to spare. In my experience it seems to take better/sharper pictures under water than out of water. It also seems to have a long exposure time as I ended up with a number of pictures that exhibited image bending and tearing, but none underwater…
It is a very handy little camera for kayaking/snorkeling/diving or whatever, just don’t expect it to take amazing quality photos, but it does float when attached to the neoprene strap, runs on AAA batteries, and it really is waterproof, I used it for several tanks of air in 30-40 feet of water.