The web has created a huge challenge for creators and copyright holders, a challenge that has created some ridiculous scenarios; take the case of the band Death Cab For Cutie being sent a takedown notice from their own record label, for posting a video, funded by said label, to the band's own web site.
The real issues are further muddied when words such as "pirated," "stolen," "infringers" etc are used. The bottom line really, is that our current copyright laws need to be updated to take into account how artists are creating new works by mashing up disparate works and then invariably posting those works to the web.
In his film RiP: A Remix Manifesto [which you can watch for free here,] Web activist and filmmaker Brett Gaylor explores the issue of copyright in the information age, and the tension that is created between the producers and users of their work. So, is it piracy or art?
From the film web site:
"The film’s central protagonist is Girl Talk, a mash-up musician topping the charts with his sample-based songs. But is Girl Talk a paragon of people power or the Pied Piper of piracy?