I've seen the GoPro in action. For the $200 price tag, I can't think of a camera that can beat it.
There is decent diving in the Dominican Republic, it isn't all like Puxlut says.
I prefer the camera + housing options to just using a water proof camera. Housings are more reliable and help take better pictures, but for a point and shoot camera it would add on about $200 to the price.
Canon, Olympus and Sony all make housings. Olympus makes the nicest housings, but they are more expensive.
http://www.bhphotovideo.com/c/search...223+4291215468