The adult industry has had to develop increasingly explicit porn as the Internet has become increasingly pervasive in modern society, and as a result, we have all become exposed to a higher degree of pornography that makes scenes from as little as 10 years ago seem, well, rather tame.
As the adult industry becomes fragmented into greater and greater divisions of adult genres, one constant seems to remain solid: that the more explicit porn becomes, the more interesting it becomes to an audience that has become rather desensitized to standard missionary positions executed in typical boy-girl settings. The modern online audience wants new angles, multiple performers, and greater extremes: all of which push directors and producers to constantly seek out the newest most outrageous content available.
As this direction reaches its apex, the line between what is explicit porn, and what is acceptable porn becomes blurred, and the industry begins to teeter on the brink of obscenity. However, this is a natural and constant evolution that continues to push porn into more and more astonishing incarnations, as society becomes accustomed to the last plateau of adult entertainment genres, and new, more shocking genres emerge to fill their place.
This all leads to a cultural question of how far this will go before no porn is considered explicit, or perhaps we will all become as fetishistic as over-sexed cultures like Japan have become.