What do you mean by waterproof? I use a Canon A570IS with a Canon WP-DC12 case for almost all of my camera needs. The camera takes great pics, has full manual settings, and has an optical image stablilizer. The immage stablizer works very well for video mode as it dampens the hand held shakiness. I've been very pleased with it as an all around camera. I also use it for water sports with the Canon housing, which is nice because it's built specifically for the camera, and the camera is designed for use underwater with settings to eliminate some of the blue tones.
The camera was ~140 and the housing was ~175. Yep, the housing cost more than the camera, but it is well built, and works awesome.
Canon has housings for a lot of their camera models, so if you wanted a nicer camera you could likely find a housing for it. This set up IMO is the best dive camera you can buy for the money, it fires my strobe well, even though it's a cheap strobe, and the camera takes great shots out of the housing for everyday use. Plus it's fairly small, which was my original reason for getting it as I have a couple more expensive cameras that are a PITA to haul around. And the reality is that anything short of low light where a big objective lense really helps, it takes just as good of pictures.
Also I would highly recomend a visit to
Imaging Resource "Comparometer" ™ Digital Camera Image Comparison Page to do a side by side comparison of photos with the different cameras you are considering.