Standards of Beauty
Slight tangent: am I right in surmising that the singles scene is one of the reasons why the standard of beauty in the US is becoming the porn star?
I believe you are incorrect. I have seen what you're talking about, and I think it's due to the incredible ease of access to porn itself. I can't remember who pointed out (in a livejournal discussion, but that's all I recall) that these days the average 20-year-old man has seen far, *far* more women in porn than he has seen naked women in real life. His eyes are used to them, in a way that he won't be used to actual naked women.
What I noticed starting a few years ago is that young men stress thinness in young women much more than they used to. I've had a young man argue with me that male preference for slender women is "hard-wired", and that there must have been evolutionary change since the days of Renoir (!), because back then guys seemed to like fatties. *head desk*
When I was a young 'un in the 70s, the young men generally assured us young women that models & movie stars were *not* all that attractive to them, because they were much too thin -- and flat-chested, which made their assurances quite believable.
In recent years, though, the style in porn and in the rest of the entertainment industry has been for young women to be skinny but have breast implants, and this has gone along with the dissemination of free porn online. I think both men & women have gotten used to seeing skinny+implants women as the standard of sexy.