I think curse words lose their power when you throw them around too much, but I've seen many movies which have had a character that swears a lot, and often it works, although I'm sure there are ten bad movies for every good one. Sometimes you can get good humor about using softer curses, like on 30 Rock when a character made an interesting combination of poppycock and hogwash.
I also think that you should be able to read the situation which you're in. I'm not offended by cursing, but I think it paints a picture, if every second word that comes out of your mouth is a curse word, I probably won't take your opinion seriously. It is however pretty powerful, when a person you never hear cursing gets over his or her threshold and finally uses a bad word for the first time in years. You tend to take them seriously at that point. But I also know that when I take my car to the repair shop, it's better to wear dirty clothes and curse a bit, it tends to keep the bill lower. This isn't necessarily true for all auto repair shops, but it is for the ones I use.
I do think that it's pretty hypocritical to use curses that sound like the bad words, but aren't them just to avoid censorship or a fine. That's often a sign of bad writing, although in some cases when the writers get really creative about it, it can actually work.
I also think that you should be able to read the situation which you're in. I'm not offended by cursing, but I think it paints a picture, if every second word that comes out of your mouth is a curse word, I probably won't take your opinion seriously. It is however pretty powerful, when a person you never hear cursing gets over his or her threshold and finally uses a bad word for the first time in years. You tend to take them seriously at that point. But I also know that when I take my car to the repair shop, it's better to wear dirty clothes and curse a bit, it tends to keep the bill lower. This isn't necessarily true for all auto repair shops, but it is for the ones I use.
I do think that it's pretty hypocritical to use curses that sound like the bad words, but aren't them just to avoid censorship or a fine. That's often a sign of bad writing, although in some cases when the writers get really creative about it, it can actually work.