Different staff members have different definitions of "profanity". For instance, our profanity filter has certain words filtered that I have no problem with, but which others are offended by.
I generally don't edit / warn members unless they're using one of the George Carlin words, or maybe if they're using the more minor words *a lot*. However, on the front page, Jeff is very strict, and will edit out any curse word.
Enforcement in this area isn't 100% consistent, and probably never could be. The best policy for everyone is to stay away from impolite language at all times. At the same time, I understand that people will slip up from time to time, and nobody is going to get suspended for the one time use of minor profanity, although depending upon the mod there may be a warning given. (Again, repeated use, or major profanity, is a different story.)
If it bothers you, by all means report it, and we'll look into the situation.