It doesn't matter if it's a CD, a Film, or manual with the instructions to build a spaceship. If you copy it, the original owner doesn't lose anything. If you don't copy it, the only one missing something (the experience) is YOU.
Enjoy!
Of course, if you happen to have some extra money for donations to creators, please do so. If you don't have that, try contributing with a review somewhere or recommending the content, spread the word. Piracy was shown to drive businesses in several occasions by independent and biased corps (trying to show the opposite).
Is it actually ethically acceptable to control distribution of something that naturally shares itself?
Before computers, it actually required some energy to copy the content of a book. With computers now, the action of reading an ebook will actually copy it from the hard drive to the ram. If your book is on the cloud, there's even more copying going on. It actually takes more efforts to erase temporary copies (ex: from local cache)!
Digital copying is not the same as physical copying.
For anyone that isn’t aware, this is the logical argument used in Cory Doctorow’s book Information Doesn’t Want To Be Free, which you can get an ebook of for free on his site.
At last we were able to create the Torment Nexus...