It's a process that combines market research, customer comments and good old-fashioned risk-taking, a task taken on by the high rollers of the adult industry. And once the trend takes off, it's then their responsibility to have the next big thing ready to offer once their current content goes out of style.
But who starts the trend?
Is it the producer who determines what's hot and what's not, or is it his customer base that clues them in? Often it's a combination of both.
"When we started less than two years ago, sites such as MeatHoles and other extreme hardcore sites were doing really well," IncredibleDollars' Glenn said. "The business model to provide extreme hardcore entertainment was simply going towards this specific trend that wasn't available for many big-tit lovers, a niche we felt we could fulfill."
However, Glenn soon found that hardcore degradation and his customer base mixed like oil and water. Big-tit lovers, he said, wanted to see girls happy and sexually satisfied, and what IncredibleDollars was giving them was the exact opposite.
"What we have learned is that big-tit lovers want to see the girl treated well and fulfilled, not being thrown around like a rag doll," Glenn said, a prime example of a company's attempt to spark a trend, only to find the consumer didn't want to buy it.
Dave at PlatinumBucks also has tried creating content themes that seemed to be a good sell at the time. Content featuring couples getting it on with people met at bars or parties is a theme he said is selling well, so he decided to test out some variations to see if customers would catch on.
"PlatinumBucks created a theme of two [single] girls picking up one guy, calling it 'Guys Lucky Day,'" Dave said. "This theme didn't involve couples, therefore it was not as much of a success as if it were a husband and wife picking up a single guy at a coffee shop."
While Dave sees couples as a hot content trend, Glenn said the MILF market has remained a premiere niche in the industry, capitalizing on the fact that older women turn younger men on. He said that when he was in college, he remembers fantasizing about being with older women.
"Many new niches have been fads, but mature triple-X content has sustained itself as a great niche," Glenn said. "Channel 69 and Homegrown were the first two companies that really broke into the market and still do a great job with this genre."
Dave said the industry is approaching the tail end of the solo-girl craze, a trend launched by companies such as LightspeedCash, that slowly started to die after a slew of smaller companies followed suit.
"It was extremely popular until every single company on the net felt they needed some solo-girl sites in their portfolio," Dave said.
He said that the sudden onslaught of solo-girl sites not only saturated the market, but saturated it with low-quality content. This, he said, is killing the niche.
Albert of SilverCash also has noticed the solo-girl explosion. Naming Steve Lightspeed as the niche's forefather, he's noted a slew of other companies following soon after, devoting their entire programs to solo girls. "That didn't exist five years ago," Albert said.
Another content trend that many adult companies are capitalizing on is reality-style porn, and it appears it's a trend that's here to stay. Companies have realized a demand for this style of content and its popularity coincidentally has followed the success of reality- TV in mainstream pop culture.
Albert said that reality content's popularity grew with Bang Bros.' hugely successful BangBus.com, which happened to explode on the scene at the same time as the first season of "Survivor" on CBS.
"When you see something is hot in pop culture," Albert said, "it follows in adult. As long as pop culture continues to embrace numerous reality-show types, like 'The Apprentice,' it will translate over to the content you see in adult."
Kink.com owner Peter Acworth is bringing BDSM onto the reality bandwagon with sites like TheTrainingofO.com, in which viewers follow a model's week-long course in submission training. Rather than creating another site similar to the fetish sites already out there, Acworth said he wanted to offer the viewer a reality site that gives incentive to come back for more.
Shot over a week, each model's training session is later edited into four separate webisodes ending with a cliffhanger much like "The Bachelor" or "American Idol." The only way for the viewer to find out what happens to the slave-in-training is to tune in again to see the next installment.
Though it's true that consumers ultimately demand the product, it's important for companies to realize that they can't do so without the inspiration of viewing original content.
"We as entertainment companies have to put them out there for the consumers and let them decide," Dave said.
There's a reason why clothing designers stopped acid-washing their jeans — nobody wants them anymore. As soon as they realize that the consumer has determined their product is out of style, they must immediately act to create something new or risk losing their customer base.
However it's not just keeping up with content trends that will retain paysite members and attract newbies — a company's content can be full of the hottest girls and the hottest sex, but if it's not offered to customers in an attractive way they're not going to open their wallets.
Adult companies such as Kink.com, Digital Playground and SilverCash realize that technology is a natural evolution in the adult industry. From filming in high-definition to offering content by the minute, content providers know that each customer has a different need to cater to.
Digital Playground co-founder Joone said it's as important to provide a top-notch distribution channel as it is to have a high-quality creation channel. As new technology evolves, people are going to want to use it to watch their content, whether it's on a new iPhone, a PDA or a mobile phone.
"Now, what content? That's going to depend on the individual," Joone said. "But we definitely wanted to have content available for every medium. We saw the iPhone coming, so we prepared for it."
Joone said he sees mobile content, whether it's viewed on a cellphone or portable media player, as a major trend to keep an eye on. It has yet to catch on in the U.S., but when it does it will explode.
"You can get your porn wherever you are," Joone said. "To have your favorite movies or your favorite pictures on there, and to be able to access it at any time, any place — you can't do that with a computer."