I'm just taking my new 5DMII out of the box so I don't yet have direct experience. However, I have "heard" through other groups that a piece of electricians' tape over the shutter release will help with the moisture issue - - that is if you want to shoot in the rain. [Non-text portions of this message have been removed]
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Re: Canon 5D MkII - Moisture Issues?
2009-04-10 by Tom Fielder