LOS ANGELES -- Music fans continued swapping songs over the Internet, though a bit more cautiously, despite the recording industry's threat this week to sue individuals engaged in digital piracy.
The threat appeared to have little effect on the pace of downloading over the most popular file-sharing services.
But the move drew the ire of many fans, driving speculation that it could ultimately backfire and encourage a new crop of file-sharing services capable of keeping users anonymous. Filetopia already promises to do just that, and another, called Blubster, is to launch Monday.
"The recording industry is not going to win if all they do is sue people," said Gigi Sohn, president of Public Knowledge, a Washington-based advocacy group on technology and copyright issues. "They can sue all they want, but that's not going to make CD sales go up."
The Recording Industry Association of America, which represents the major recording companies, said it would file several hundred lawsuits against individuals within eight to 10 weeks seeking financial damages of up to $150,000 per copyright song.
In the past, the industry went after the file-sharing services themselves, succeeding in shuttering pioneer Napster. But newer services like Grokster and Morpheus have managed to dodge the courts so far by decentralizing their systems and arguing they had no control over usage.
The RIAA hopes that by going after users directly, they can end the rampant piracy blamed for a three-year slump in music sales.
Nonetheless, use of file-sharing services appeared unchanged Friday.
Kazaa, the most popular software for file sharing, saw a significant decline in user traffic during the first 10 hours following Wednesday's announcement by the RIAA. But traffic bounced back within 24 hours.
From Wednesday afternoon to Friday morning, the number of users signed on to the FastTrack network -- the system that supports Kazaa and Grokster -- fluctuated between 3.4 million and 4.4 million, according to figures reported by Kazaa.
"The numbers have been consistent-to-normal fluctuation," said Richard Chernela, a spokesman for Kazaa parent Sharman Networks.
Grokster saw downloads increase Thursday between 5 percent and 10 percent, said company president Wayne Rosso.
Recording industry officials said Friday they don't expect their campaign to produce change overnight.
"This is a long-term effort," said RIAA spokeswoman Amy Weiss. "We are committed to communicating the message that offering copyrighted music online is illegal. It hurts artists, songwriters and everyone else who brings music to the public, and we will hold those who engage in this activity accountable."
Yet the campaign could result in the proliferation of file-sharing services that outfox efforts to detect the users' identity.
"If the recording industry succeeds in their goal of making large numbers of people feel unsafe in their file sharing, it's a safe bet that someone will come along to fill the sudden demand for an easy, safer way to use P2P," said Adrian Lamo, 22, a communications researcher from San Francisco.
For now, many users of file-sharing services said they took some precautions, but remained undeterred.
Others hoped to skirt the RIAA's sweep, which is initially targeted at those who share "substantial" collections of MP3 files, by simply disabling the sharing feature on their software -- something the RIAA hopes will mean fewer songs available on the networks.
"I turned (the feature) off because they're on their witch hunt, and I think the witch hunt will die off and prove to be just that," said Jeff Gregory, a Web editor in North Palm Beach, Fla., who uses Kazaa.
Gregory, 32, estimated he has 600 songs downloaded on his computer -- and he intends to get more.
There were about 10 million fewer files traded on FastTrack between Wednesday and Thursday afternoon, though the difference amounted to a decline of only 1 percent.
"That number should drop off over time if the deterrence is having effect," said Phil Leigh, an analyst with Raymond James & Associates.
Sohn said people won't really get scared until RIAA starts filing its lawsuits. But she warned that the industry risks consumer backlash if it sues "every Tom, Dick and Harry with a handful of songs."
Leigh said the industry's strategy overlooks the impact of CD burning. If the industry squelches file sharing, he said, young music fans will simply trade copies of CDs.
While such a scenario would be an improvement for an industry now seeing millions of music files shared worldwide, Leigh said it underscores how the exchange of music on some level won't go away.
There are 200 million CD burners in use currently, Leigh said. "And the kids are not going to stop using them."