In case its of any interest, I know of no professional photographer (above water) shooting digital who does not shoot Raw (there will of couse be some, but I personally don't know them) unless there is a very good reason (sports photography or where speed is of the essence). Although none of them drive Ferraris (being mere photographers like myself), I'm sure that if they did they wouldn't drive them at 30mph!
If a camera supports it, it is well worth shooting both Raw and jpeg if only to indicate what the camera thinks that the processed file should look like. Often this is different to how PS thinks it should look even based on the camera's settings. And of course it also depends on what you are shooting and why. If everything is under the same lighting then a batch process is brilliant, but for underwater where there is so much potential for variation, and, perhaps more importantly, where the camera is operating in lighting conditions for which it probably wasn't designed, I can't imagine shooting anything other than Raw - it simply too versatile.
There will of course be more Nikon versus Canon debates (a healthy market is one where there is choice), which housing is best, and which raw converter works best. I very much doubt that the jpeg vs. Raw debate will survive as long as the others though.