Success in the modern age is marked by two things: oversaturation and inevitable backlash. As something is recognized as being good or entertaining or lucrative, then many lampreys suddenly attach themselves to the underbelly of the main success. They ape the creative talent, the marketing, the pitch, the layout, the look, the hook. Catchphrases are spun out and apparel is adorned with recognizable images from the successful venture. Late night talk shows and morning zoo crews make lazy references and inept impressions of the successful venture. Everyone clings to the successful venture - pushing it into more markets and spinning it in novel - if ridiculously unnecessary - ways.
Then, when the last branded bar of soap or hollow script for the TV spin off rolls off the assembly line - the backlash begins. In fairness, it is not the successful venture that people are angry about; it's the constant reminder of the successful venture. The endless hype and pimping and cross-promoting and synergizing and Halloween costumes and frat boy imitations. The neverending loop of YouTube parodies coupled with the hours of proselytizing by fans that need you to "get it." It's all of the ephemera surrounding the successful venture that causes this backlash; the resentment of enduring all of these unoriginal interruptions that smack less of the fun and unique property and more of the soulless and derivative cashcow that it became.
Sometimes the creators of the successful venture buy into the hype - and so they get torn down with it in the Backlash Phase. Sometimes the sales figures for new revenue streams or diversified audience shares are so enticing that creators and their corporate barons willingly sacrifice the successful venture. Who knows when the next hit will come, so everyone pile on this thing now! Everyone releases their version of a remake of an 80s cartoon with scores made up of repetitive bellowing of deep bass notes, presented with the poster in blue and orange, and the making-of-featurette with untrained celebutantes boasting of the integration of the latest CGI trickery into this "ride" - all while pimping the tie-in to the specific fast food chain and soon-to-be-forgotten pop music group. That original spark, the successful venture that forged something new and exposed people's interests to the harsh light of capitalism, becomes awash in its descendants, indistinguishable to most people's hate, and relies on nerds to argue for its exclusion from the pack.
But what does this all have to do with graphic sex on film? The answer...might surprise you.
Porn films have been around since the dawn of the movie camera. Hell, even before then with various pornographic zoetropes. Don't believe me? Watch any documentary, reality TV series or midnight special on "adult films" and someone will mention it. Seriously - a talking head in any of these presentations will, at some point, talk about how USA is a "kinky nation" and that sex has been synonymous with film since the day Muybridge made his first zoopraxiscope. I'm not disputing it - I'm just saying shut up about it, we hear you already.
What's really interesting about porn films is all the permutations they have gone through as society shifts and changes. From nudist camp pictures, to marquee titles like Deep Throat or Behind the Green Door, to ushering in the technology of VHS over beta to supporting the growth of the web like a horny Johnny Appleseed. Porn is constantly changing - even though the depicted acts themselves are fairly static with little variation or revolution through the ages. As Hooper says in Chasing Amy:
Men need to believe that they’re Marco fucking Polo when it comes to sex -like they’re the only ones who’ve ever explored new territory. And it’s hard not to let them believe it...The world would be a better place if people would just accept that there’s nothing new under the sun, and everything you can do with a person has probably been done long before you got there.
So despite the fact that almost every sexual act - no matter how deviant or socially frowned upon it may be - is a tale as old as time, how does Porn stay relevant? Well, on the one hand (no pun intended) - we're a kinky nation and we like to watch ourselves some tits and dicks floppin about. So the core product - fucking - never goes old. But the packaging is where creative types must make their mark and it's where filmmakers, studios, producers and even the actors have to do something to stand out.
The Internet is the "newest" packaging for porn - all the colors of the sexual rainbow delivered directly to you in the nonjudgmental confines of your comfortable bedroom or surprisingly isolated office. But even within the evolving technological trappings of the porn delivery system, there are styles and themes that run throughout. Trends that not only mirror the decade in which they are popular but also bring with them a new sense of aesthetic and erotic that, come decade's end, will be dismissed as obsolete or taken as a "given" moving forward. The lavish spectacles of the 70s gave way to the yuppie approach of churning out videotapes of the 80s, to the attempts at being different and new in the 90s with DVD technology, to the early 00s marked with webcams, celebrity sex tapes and a realization that you're not a freak but a part of a community (of freaks). 
The latest (and current) trend in porn is the irony drenched touch of hipster that is the XXX Parody. Formerly the source of many ribald Fox jokes - "Shaving Ryan's Privates," "Beverly Hills Cock," etc. - XXX Parodies have become a cottage industry and thriving genre within porn. XXX Parodies take a well known property (like a movie, TV show or public figure) that has some sort of cultural cache - either formerly popular or currently en vogue - getting porn stars to portray crude caricatures of the principle characters and then having these characters bump more uglies than in a library of fanfic. Companies have sprung up to create XXX Parodies of The Office, 30 Rock, Anthony Weiner's Scandal, Seinfeld, American Dad, The Simpsons, The X-Files, Presidential Campaigns, Star Trek, Batman and many, many others.
Porn production companies are offering up these XXX Parodies for a very simple reason - they have the (incredibly modest) means for legal defense, staffing casts and crews and investing in some sort of production design (that includes costumes, make-up and sets). These trappings - when combined with the familiar characters/properties - are enticing for viewers and cannot be offered by the thousands of reality/webcam porn movie houses. But the irony well will run dry as will the source material - after all, how many volumes can they possibly make of Sanford & Son: A XXX Parody? So what then? What will be the next move for Porn Studios? The answer is as obvious as it is cliched: Porn's next step is making "real" movies that will incorporate explicit sex scenes.
The immediate disclaimer is that I'm aware that the "mainstreaming" of porn has been discussed to death and people have been predicting an intermingling between pornographic films and more common cinematic fare since at least the 70s (in fact that's one of the main driving forces in PT Anderson's Boogie Nights). And the reality/cheap skin flicks of internet production houses will always be around. Genies don't go back in bottles, after all, so for those that are so inclined - the "reality" porn will continue. But, once the shooting wraps on Thomas the Tank Engine: A XXX Parody, large Porn Studios (New Sensations, Hustler, Vivid, etc.) will need to have the next product ready to go. So why not take the next logical step and take the "professionalism" of productions of these parodies and use that for original films?
Meanwhile, on the flip side of the cinematic coin, there is a rise of explicit sex scenes in "respectable" films - most indies that are usually well received by critics and occasionally audiences. Shortbus, Nine Songs, The Brown Bunny, Irreversible, Blue Valentine, Antichrist have feature realistic (if not literally real) sex scenes with a mixture of professional actors and amateurs. Add in to that the rise of the penis in film - there've been more cocks in comedy in the past decade than the preceding 60 years of films combined - and you have people get more and more comfortable with real-ish depictions of sex.
It won't be an overnight change - it'll be a gradual shift as a few titles are released each year. And make no mistake - it'll still be on discs and the internet. I know that China's 3D porn film did well - but that's like borderline entrapment for a slew of public indecency stings.
Again, the process is slowly taking shape around the XXX Parodies - scripts written, characters tweaked/formed, marks hit to convey characters (a necessary move when you have porn stars that do not resemble their pop culture opposites). Obviously, the first batch of these original porn films will have to be non-challenging fare that appeals to many people while also avoiding any cost prohibitive demands. Which means - as it always does for large appeal - comedy and horror films. Because, no matter how many explicit sex scenes take place in "respectable" cinema, people will have to be eased into this new format.
But why would talented filmmakers want to work in these hybrid porn films? Because of the freedom that comes with the lowest of expectations and demands. Porn films require a set number of scenes, with a prescribed list of iterations and interactions (man/woman, woman/woman, man/woman/man, etc.) - if you can deliver those scenes and you can stay on budget, then you can pretty much do anything else. The movie is already rated X - you don't have to worry about ratings boards, or corporate sponsors. Mainstream movies require tailoring scripts to hit the broadest demographic, without violating any of the MPAA's arbitrary decency rules, or pissing off potential investors, etc. These concerns do not pertain to adult films. Ironically, mainstream movies are just as beholden to that checklist of scenes - often referred to as "trailer moments" - which are the handful of scenes to throw in the trailer to get people interested in your film.
If your movie has those 5 or so trailer moments, then that's great; now stay on budget, don't cuss too much, and don't make fun of Taco Bell because we have a tie-in promotion with them. In the adult film world, when you've got nothin, you got nothin to lose.
Think of it: instead of finishing up your dirty shameful lonely business and then being thrown into a crudely edited scene or some terrible stilted dialogue, the viewer can then focus on the story that leads up to the next scene. Interesting characters discuss original ideas using clever bits of dialogue. Suddenly you're engaged - you watch the whole thing. The XXX Parodies are definitely dipping of the toe in the pool of combining these two schools of film thought: many non-pervy sites have reviewed the versions of Star Trek, X-Files and Batman and found that they're actually not that bad as far as fan fiction goes. So make the next logical step and make a wholly original film that contains ejaculate and exposed lady parts while also being an entertaining film on its own right. History will be much kinder to trailblazing pioneers than it will to ironic references and half-hearted head nods to establish pop culture.