I like this discourse on the f-bomb from the Dead Youthpastor Walking blog:

I find people who always have to cuss to get their point across to be fairly stupid. I recently encountered one such person and wrote him off completely because of his lack of self control.

But when is it appropriate? I think when you truly have something to be passionate about, to express extreme confusion at something; and most definitely not when you're talking directly to one person and addressing them with said f-word. Like I said, I think people who throw the f-word around without regard for its influence on the crowd are ignorant and not worth my time. I think if David, Job, or Jonah had the f-word at their disposal... it would be in our scriptures along with many of the other lewd references. Not sprinkled throughout like paprika... just placed in just the right spot to convey the tremendous combination of angst, confusion, and disgust at something that punctuates a low time-- not just a desert time, but a devil-standing-next-to-me-in-the-desert kind of time.

I think we spend a lot of time working on an image for the church... an image of infallability, of self-reliance for holiness. I know, they'll say "oh, our holiness comes from above..." -- and yet if you cuss that holiness just runs away like enron stockholders? Come on. Holiness belongs to God and no amount of vocabulary will secure or hinder it. It just is.

I think a moderate number of extreme times in our lives merit extreme phrases. I believe our forefathers through the scripture made that quite clear. And yeah, I still believe I tend to write people off when they cuss at me.