Pro series Nikon digital cameras and lenses do have amazing weather resistant seals but I doubt they were designed to sit in what amounts to a horizontal salt water waterfall which is what you can get on board a fast moving yacht.
I have been trying out a camera waterproofing product called Outex.
The Outex system is based around a latex camera condom with glass ports for the lens and viewfinder.
Once enclosed the camera can be pretty much used as normal, under water to a depth of 10 Metres.
You have to remember where your buttons are and you can't review the images on the LCD screen of couse but it does allow you to hold and operate the camera as you are used to.
It is a finicky thing to fit to a large camera like the D3s. The whole Camera/lens arrangement must be forced through the lens hole in the latex bag.
Not perhaps as easy to fit as a solid waterproof housing but a damn site cheaper, lighter and more tactile, and frankly I don't need the ability to take my camera under water, I just want to not have to worry about it when it gets a dousing.
Here I am onboard the Emirates Team New Zealand AC72. D3s in the blue Outex cover.
... plus a few from on board CAMPER in the race from Auckland to Fiji.