Originally posted by AstroDave I remember reading somewhere years ago, that if you dropped your camera in the ocean, the first thing to do was to rinse it immediately in fresh water. Then, head for the repair shop.
As noted above in this thread, pure water is pretty much a non-conductor, and if electronic gear gets wet, it will often survive if dried fully before being turned on again.
Generally this is OK, but with the camera it might be a little tricky due to 1) the mechanical parts involved and 2) the optical surfaces.
I have a friend whose camera (a Nikon D200) fell in a river; the camera didn't work afterward, but after sitting and drying out for a couple years (she had already bought a new one), it worked again. But she didn't really do anything with it at that point, so I'm not sure how clean the viewfinder/sensor/mirror was.