Back to the OP's original question:
What camera to get? First question -- What do you want to do with it? Are you primarily interested in taking "good" images (see my prior post -- at least I think some are "good") or are you primarily interested in taking "very good/great" images?
Second question -- What is your budget?
If you want "great" images (of the "I want to sell these" type) -- I'm convinced you need a dSLR and at least two strobes. The jump in pure image quality due to the choice of lenses just makes a dSLR a "better" camera than any Point 'n Shoot. Yes, the most important piece of camera equipment is the eye behind the lens BUT, the lens is number two and does make a huge difference.
If you are willing to be satisfied with merely "good" images, then go the Point 'n Shoot route due to the cost and flexibility of them -- not to mention ease of use and ease of transportation. To determine WHICH Point 'n Shoot -- I'd suggest looking at the following:
a. How "wide angle" is the native wide angle? For example, my Canon S80 has a 28mm wide angle (35mm equiv) which is why I went with it over the Olympus SP350.
b. How "macro" is the native macro? A lot of shooting tends to be macro (and this is where the dSLR's shine) so how good is the "macro mode" on the P n S?
c. How much control will it give you? Does it have a manual mode? Does it have manual focus? And if so, how easy it is to use when housed? (BTW, I didn't consider the ease of use of those two items when my S80 is housed and I wish I had because it is near on to impossible to change settings in manual mode with my housing in cold water -- i.e. with dry gloves one.)
d. Another issue I'd look for is RAW capability. I know it is a big thing for a lot of people but, for me, it is not all that important but then I don't use RAW when shooting with my dSLR on land. (Also, most of my UW shooting is done with a strobe so I'm not doing the blue color correction.)
e. The last issue is video. I don't use video very much but I'm very happy I have that option with my P 'n S. For example, when we dropped off the boat into a pod of dolphins I shot a few still and then switched to video and got several priceless minutes of us playing with the dolphins -- not to mention a much earlier video of a humpback doing a loop and swimming around us. Video is a very good addition which most dSLR's don't provide (the new D90 does, right?).
Anyway, to the OP, those are my thoughts -- and I still don't have a clue what is the "right" camera for UW photography -- although I believe there are many that are the wrong camera!