Research firm Yankee Group has said that the sale of X-rated content for portable devices could be worth US$200 million annually by 2009, fueled in large part by the new video-capable iPod as well as cell phones that can play video. Mike Musgrove, writing for The Washington Post, reported on that development on Tuesday, noting that while Apple needed 20 days to sell one million videos on the iTunes Music Store, softcore porn site SuicideGirls took a week to reach that number of free downloads.

Playboy and Penthouse magazines have already said they will soon sell content formatted to play back on iPods, according to Mr. Musgrove. In response, the Cellular Telecommunications & Internet Association said last week that its members won't offer adult photos or videos until a rating system similar to the one used by the movie industry is in place.

A Sprint Nextel spokeswoman told Mr. Musgrove that the company doesn't plan to offer content "racier than what is on prime-time television," while a Virgin Mobile representative said only that her company has no plans to sell adult content.

Whether cell phone carriers get on board or not, porn industry veteran Harvey Kaplan told Mr. Musgrove that companies are looking for new markets to exploit. Mr. Kaplan said that his new company, Xobile, has seen "fast and furious" growth of the sales of content for portable devices. He sells his videos over the Internet and noted that he will continue to do so, regardless of what the cell phone carriers decide to do.

However, Ralph Whittington, a former Library of Congress curator, is dubious that these new markets will be popular, remarking: "I can't see anybody wanting to watch while they're sitting at the airport." In response, Wired.com columnist Regina Lynn pointed out that such avenues are perfect for those who don't want to use desktop or laptop computers to download such content.