Anyone who thinks profanity is lazy or cheap needs to watch 'In the Loop', because this movie turns cursing into an art form. Beyond that, it's a great parody of how government policy is shaped by wet-behind-ears kids.
The main draw of this movie is actor Peter Capaldi, who plays Malcolm Tucker, a thinly-veiled parody of former UK Director of Communications Alistair Campbell. He is by far the most entertaining / funny / horrifying part of this movie. He spews out angry, well-versed Scottish-tinged vitriol unlike any other character I've seen on screen. I don't think I'm allowed enough room to list all my favorite quotes from this movie, and 95% of them would come from Tucker's character. Beyond that, this wouldn't be a G-rated review if I could list all my favorite quotes (the C-word would figure pretty prominently). If you like fast-talking British comedy and all the cursing that might come with it, you will like this movie.
Beyond the draw of Tucker's character, this movie is a great comment of the forces driving government policy. The plot involves a drive by the US to invade an unnamed Middle-Eastern country, and a bumbling UK Minister is drawn into the debate by virtue of his own ineptitude. The movie doesn't try to be preachy or overly political about current North American / UK policy in the Middle-East. Instead, it uses a contemporary situation to satirize government.
I think if you're a fan of Brit comedies like 'I'm Alan Partridge' or the UK version of 'The Office', you might really enjoy this movie. But even if you're unfamiliar with those and just like a good satire, this is worth a watch.