I'm speaking as part-owner of an indie game company here, so my opinion is likely biased, but in general as far as I've ever seen, most "piracy" numbers are a bad combination of fantasy, worst-case assumptions and wishful thinking.
The firmest numbers I've ever seen given were for a BBS in Ottawa a decade or so ago. It got raided and shut down, and the powers that be announced that it had been responsible for hundreds of millions of dollars in piracy. I can't remember the exact figure, but it was huge.
So, you might wonder how they got the numbers. Since there weren't detailed logs, they added up the retail value of all the software on the site (Microsoft Office, Windows NT (workstation and server), lots of other expensive commercial packages), and then multiplied that by the number of dial-ins in the log. The assumption being that every time someone dialed in on their 28.8K modem, they were downloading the entire archive. Even if that person had logged in many times before.
The BBS was run by a high school student for his circle of friends, none of whom would have bought any of the software on the BBS had it not been available free. The "hundreds of millions of losses" were *entirely* fiction. The "lost" money never existed.
For the longest time, the publishing industry has taken advantage of the "piracy" sticker; it sounds like something you'd want to be against. They've made up loss numbers from whole cloth and bong hits, and if you question them they harumph that the numbers are only estimates and could be *even* *worse*. It says something about their behavior when they've managed to legitimize piracy to the extent they have; the term now has as much cachet as it does stigma.
Someone pointed out recently that the doctor who killed Michael Jackson got four years for it, but if you pirate his music you'll do five years in jail under SOPA/PIPA/ACTA. This is where we are now; you're better off getting charged with manslaughter than piracy.
I'm not sure what's to be done, personally. In Canada the two political parties most likely to run the country (Conservatives, Liberals, the former are currently in power) have been in the back pocket of the publishing industry for decades. We have occasional public consultations about copyright, and they've shamed the government into inaction several times, but it has been defense in depth; we're pushed a little further back every time.
As an indie developer, I can tell you the publishing industry is just flat-out lying when they tell you it's about the artists. The artists are getting shaken down as badly as anyone else. What this is about, what this has always been about, is control of distribution. The publishers have been exploiting their distribution monopoly ruthlessly, and now that it's threatened they're on the rampage.
So remember, we aren't talking about the "content industry" or the "media industry" here; most of these corporations don't *make* things. We're talking about the corporations who own distribution monopolies on things that other people make.
The market will destroy them eventually; they aren't useful any more. The internet has seen to that. The question is, what do we do to limit the damage until they finally die?