Editor's note: The following review is about pornography. If the subject itself offends, please stop reading. Why write about it? First, because pornography is "intimately linked with the evolution of communications technology," as one history professor interviewed puts it. Second, because the porn industry, like the music and newspaper industries, faces a technological problem and doesn't know what to do next.

I was 29 and had been living in Los Angeles for nine months when I took a job with Larry Flynt Publications. Technology was the last thing on my mind, but that would change quickly. The most famous of the 20 magazines under the roof was Hustler, the raunchiest of the three big American skin mags. But within a year of my arrival, in 2000, some of the less popular titles folded, and it was clear that a shift was in the air.