I recently spent 65 some dives in the Philippines with my new Olympus 5 meg point and pray camera. Great results. See my pix.
Air Conditioned room, dried everything with camera and housing laid bare. Transported it in zippered cordura bag.
Blew it out with pressurized air... or not.
Wiped the interior with tissues... or not. Toothpaste treatment.
Water temp: 83 degrees
Air temp: ranged from 80 to 90 degrees.
Result? If you use the flash a lot, these things fog the lens port.
Annoying at all the wrong moments- usually happened at 55+ minutes into the dive, I was shooting a lot- it's the Philippines, after all. Never cleared until I got back topside and aired it out.
Next time- silica dessicant packs scavenged from medications and electronics.