There's always been a distinction between indoor and street-level prostitution, and advances in technology have increasingly separated the two, said Ronald Weitzer, author of "Sex for Sale: Prostitution, Pornography and the Sex Industry."
Not only can prostitutes and escort services now run more efficient businesses, but they can leverage word-of-mouth advertising in new ways to build their brands and troll for clients. Online social communities built around the escort and sex worker industries can solidify customer loyalty.
"It's commercial, but it's also social, so people do really form relationships," says Audacia Ray, author of "Naked on the Internet: Hookups, Downloads, and Cashing in on Internet Sexploration" and a former sex worker.
"Clients become buddies," she said.
There are a host of online message boards where clients or potential clients can discuss, rate and exchange information about individual women.
A recent rating of one woman on the escort-review site http://www.bigdoggie.com reads: "She is the real deal. She's bright, funny, enthusiastic, beautiful, flawless body, really loves what she does."
Another woman got a bad review -- not for her physical shortcomings, but for her communications etiquette: "... didn't return calls or e-mails. Irresponsible."
Such sites are natural places for escorts or prostitutes to advertise, linking to their own Web sites, a technique many sex workers use, Ray said.
Technology also eases the business-end of things, Weitzer says. While clients are surveying potential companions, escort-service managers can look into clients with a background check or even a simple Google search.
Payment is easier, too.
"It's often convenient to have an account established with a balance, so if you have the last-minute urge, you don't have to worry about getting money into the account," says Norma Jean Almodovar, executive director of the sex workers' rights organization COYOTE ("Call Off Your Old Tired Ethics") in Southern California.
Emperors Club VIP, the high-end prostitution organization Spitzer allegedly was involved with, was brought down when banks noticed frequent cash transfers from several accounts and filed suspicious-activity reports with the Internal Revenue Service, a law enforcement official told The Associated Press.
The accounts were traced back to Spitzer, and public-corruption investigators opened an inquiry.