It did not, it seems, take peer-to-peer file-sharing sites long to rebound from music industry threats to start suing individual downloaders for copyright infringement, which cut traffic to many of the biggest sites earlier this month.
   After that initial dip, traffic to the sites has rebounded to normal levels, and that has led Jupiter Research to worry the industry even more.
   Yesterday the group cut its online music market forecast, one year after predicting that the market could reach $5.1 billion by 2007.
   Instead, Jupiter says, that number will only reach $3.3 billion by 2008, a difference of some 34 percent.
   That still represents a big jump from the less than $1 billion online music is expected to generate this year.
   But after a three-month period that saw the debut of the successful Apple iTunes site, which sold 2 million downloads in just two months, and the sharp downturn of traffic to file sharing sites Kazaa, Morpheus and others earlier this month, the revised figure is a disappointment.
   Jupiter says that online music subscriptions and downloads will total roughly $80 million this year.
   According to Jupiter data, music industry warnings have not had a big impact on surfers’ downloads. Only 17 percent of those adults surveyed said that they had changed their file sharing habits because of recording industry threats.
   That seems clear from Nielsen//NetRatings’ most recent weekly rankings. Three weeks ago, the company reported that traffic to Kazaa had dipped 15 percent week-to-week to 5.6 million
   For the week ending July 20, traffic to Kazaa had sprung back to 6.5 million users, a 14 percent increase since July 6.
   The recording industry thus must be happy over, ironically, the relaunch of Napster, which, it was announced yesterday, will take place before December.
   This time Napster will be a legitimate service presided over by Roxio. The media still seemingly can’t get enough of the Napster saga, and that could help boost sales and interest in 2004.
   There are certainly enough other potential online music sellers hoping to capitalize on Napster’s publicity blitz in the next six months, just as many began considering offering services after the phenomenal first two weeks of iTunes.
   America Online will start a music service this year. Amazon.com, RealNetworks and Buy.com also have discussed offering them, though they do not have definite launch dates.
   Musicmatch said Monday that its download service, featuring agreements with nine labels, will launch this fall.