Yeah, in the U.S. version they bleep out his profanity. In the UK version they don't. However the UK version is less dramatic...

I've watched all the KITCHEN NIGHTMARES from the UK and Fox. The UK ones seem to have a little more variety -- the problems Ramsay unearths are more varied and the format is a little less streamlined and repetitive. BBC America bleeped out as much profanity at Fox. On the other hand, Fox.com eliminates most of the commercials, and it's always instructive to watch Chef Ramsay at work!
People say Ramsay mistreats the little people, that he is as destructive in his criticism as Simon Cowell. I disagree. His job on KN is to resurrect a failing restaurant, which means he has to diagnose its ills and prescribe treatment. The diagnosis means telling some home truths to owners and chefs. The prescription means finding the positive elements and emphasizing them in a new strategy, and he teaches by example. Usually, at least within the format of the show, he is successful. Cowell's job is to eviscerate performers who have no place on a national-network show.
I watched an episode of HELL'S KITCHEN, a sort of SURVIVOR-type show for aspiring chefs. Ramsay is a martinet with these competitors, but he does teach them how (for example) to make fresh pasta. He obviously still has the chops, which gives him the right to criticize others' inadequate technique.