I brought my Olympus 1030SW on a recent river rafting trip. It worked just fine. It's a compact camera with the image quality issues that go along with that, but the waterproofing worked 100%.
Iff you get one:
Don't touch the lens or try to clean water from it. It seems to have a water-repelling coating, so when you turn the camera on and off to actuate the lens cover, the water will be removed.
Buy the $12 float strap. You use a float bob with your boat keys for the same reason: the camera will sink otherwise. The float strap isn't that big but has plenty of buoyancy for the camera, and has a loop for carabiner clips. Tip if you're wearing a life jacket: clip the top buckle of the life jacket through the camera float strap. That way the camera will always be hanging ready and right in front of you.