Poor Guns N’Roses. This week, just as the band are on the verge of releasing their long, long, long, long-awaited album Chinese Democracy , right under their noses a new song is unofficially “leaked”. The song, Better , has even been receiving radio play in the US despite its being only a demo. Reacting to the leak on their band website, the keyboardist Dizzy Reed said: “Hearing a demo on the radio really sucks.” A fair point, especially when you have been labouring over an album for 12 years — and spent around $13 million (£6.7 million) in the process.

G N’R are not alone. This week Kylie spoke out on her website to deny any involvement with the “leaked” track Excuse My French. Quashing rumours that she was having a pop at her ex, Olivier “Love Rat” Martinez, a post on kylie. com reads: “Kylie has never recorded a song by that name.” Which is a shame. Happily, the post’s wording does prompt one to speculate on what song titles she has been working. No doubt the shiny pop princess is too classy for something along the lines of You A**hole .

So why is the internet so leaky these days? In Guns N’Roses’ case it seems to be Harley-Davidson’s fault. “We were doing a commercial,” Reed moans, “Harley was going to do a version using Paradise City and another using Better. Their website even had a version up for, like, one day with Better but the version that they had was an unapproved demo. That’s why it was removed. The version getting airplay is that demo . . .

“For the record, absolutely none of the songs that have been leaked have come from the band or our organisation. None of the songs that have been leaked are anything more than works in progress.” So, it wasn’t so much leaked as put on a popular, well-used website, then recorded by fans and played on air by net-savvy DJs. If the band were so concerned about the quality of the track, perhaps they should have thought about that before accepting Harley’s cheque.

The source of Excuse My French is less clear. A breathy dance track, it ticks the Minogue boxes, but the heavily doctored voice and dirty-laundry lyrics don’t convince. But why would someone want to put out a fake Kylie track?

“Putting out pretend tracks is an unusual phenomenon,” says Ben Cardew, of Music Week . “People do it to fool people and get their music heard. Kylie would certainly be the most high-profile artist it has happened to. A few years ago some phoney Daft Punk songs duped people for a while, but Kylie has such a distinctive voice, it’s hard to fake that.”

With tracks by Michael Jackson, Justin Timberlake and a whole album in the case of Bloc Party all surfacing in the past month “leaks” are yet another thing over which beleaguered record execs can tear out what hair they have left — or are they?

“It goes back to the old argument about how file-sharing affects sales,” says Cardew. “Take the Arctic Monkeys — all their demos were online and yet their album was the fastest-selling debut of all time. The same with Bloc Party — their current album was leaked on to the internet two months before its release, but that didn’t stop them going Top Ten in the UK and the US.”

So how do things get “leaked”? Even if the unofficial industry line is that online hype is not always a bad thing, it seems unlikely that record-company employees would be responsible, since creating legitimate, time-tabled buzz is their job. Most likely it is simply down to advance promo copies being circulated among the media. Or, in the case of Axl and his chums, handing over your tracks to global brands for use on their website.

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