Nudity In Films - Is it acceptable?

I recently uploaded my thoughts on the new Scorsese film 'The Wolf of Wall Street'- Fantastic film and highly recommended for those who don't mind a bit of sleaze- and naturally afterwards I discussed it with my flatmates. They were divided in their opinions, however the cause for a lot of criticism came from the frequent nudity that the movie displays.

So I put forward this question; When is nudity acceptable in cinema?

Now here's where the problems start to arise, when there is an absence of clothing in a movie it is 99.9% likely that it is going to be a woman who gets her kit off, and is that OK?
...I'm not sure.

I believe that female nudity in cinema can be justified, for example, if she would have got naked in real life to do a certain activity that she is rein-acting on film then for me it's actually annoying when a bra is conveniently left on. The thing is that in the same scenario a man should be naked too, and all too often a sheet is choreographed in to cover his intimate areas while the woman's breasts are on full display.

Nudity for the sake of nudity is wrong, if a woman is in a scene just so she can take her clothes off- and her purpose is to be nothing more than a sexual object- then it is shameful.

Audience is key when it comes to this issue, and it is also where a lot of people can slap down the feminism card. When making a movie you have to understand what the audience wants- male, female, young and old all want different things and it would be impossible to make money by pleasing everyone.

To put it into perspective I shall use myself as a case study. If there was a naked woman on screen I am less likely to cringe or look away than if there was a full frontal shot of a man. For me neither of these images are attractive, but I can bet you that a man would have exactly the same reaction with the only difference that he is seeing the female form as a desirable object.
Film directors exploit and sell this. I don't mind seeing a naked woman, not because I am attracted to her, but because I am used to it.

Social conditioning has integrated the idea into our minds that it is less shocking to see a woman without clothes than a man. The Sun newspaper has page three models topless for the world to see in order to cater for the male readers, but a key difference is that a topless man is not shocking, just because their chest area is less voluptuous. If you were to put a fully naked man on page three however, I am sure complaints would be in the thousands.

I know it's not right, and it probably won't change any time soon. So for now prudes will be prudes and various industries will continue to tread the fine line of the naked body being displayed as art or porn.