If you take out the games (as I mentioned above), the entire BSD userland + kernel has less swear words that the Linux kernel alone. I find it hard to believe that all of the BSD contributors have such sqeakly clean comments. I have a feeling the FreeBSD core team might do some 'filtering' before committing changes - or they might ask all of their contributors ahead of time to try and keep the language clean.
In any case, I'm pretty sure the dev team makes a conscience effort to keep the code fairly clean. I saw this quote on the BSD forums...
" Actually, I'm sure I've seen a commit to the tree before which was just to remove a foul word put in by a developer."
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