Anybody that places confidential or private information over the internet onto a server not controlled by a formally regulated organisation or system and without an appropriate level of encryption or access control, is asking for that information to appear in the public domain.
This is not to suggest for one moment that BK would abuse its position, simply that the medium itself is insecure.
Simply put... if you have something to hide, dont hide it here.
In the same way you would not discuss your love life, or office conspiracy et al where it could be overheard.
Then whether or not your messages can be overlooked becomes largely irrelevant.
Having seen some of the posts, personally I feel anyone who could sift through all that rubbish for a nugget of interest deserves a medal.