Sorry to hear about the loss. Lost my DC500 last week on my first dive of our week long trip to St Thomas, because I failed to secure it to the D ring, and slid the lanyard up my arm. Sometime later noticed it was gone, and ran my air to zip re tracing my path. Unsuccessfully. Really bummed.
I got it back! 2 days later we were able to return to the same site, and one of the divers in my group knew I had lost it and he spotted it. One in a million chance, but it had hung up on the coral.
I hope you get your DC600 back too!!!
My Girlfriend lost a camera under certain circumstances in Mexico last year... It was on a drift dive with Bull Sharks, so some awesome pictures were on it. Halfway through the dive she noticed it had somehow come undone and was gone, but the dive was too good to surface, so we carried on..
In the end, the boat following our bubbles, saw the camera come up (it was positively buoyant), and picked it up. Needless to say we were relieved, and the boat crew got a nice tip
I guess we've just had bad luck with Cameras...