I'm actually surprised that less people are defending TPB. It's theft, but it's so prevalent and prolific, I'd have thought most of you were pirates. Thucydides post makes it seem like he's pirated very little and feels really guilty about it...
If it helps, I personally pirate enormous amounts of music, movies, and television. The only music I buy is from more obscure artists that I feel really need the money, but otherwise the rest of my roughly 7000 songs are completely and utterly pirated. If I didn't pirate, I wouldn't buy the music, because I don't have the money to buy 7000 songs. I'd likely rely on internet radio. The only live shows and concerts I've been to are to bands that I've only discovered through pirating.
I probably have about 50 pirated movies on my hard drive, many of them I've seen in theatres or have rented, and they have no effect on how often I go to see new movies in theatre. If anything, they may have increased the amount of movies I see in theatres if I'm eager to see a sequel of a good movie, though for the most part I'm extremely wary of sequels. If I didn't pirate movies, I'd probably rely on watching movies with friends so we can all see each other's collections.
I pirate a few shows now and then, but I don't generally watch a lot of TV. Typically I do this to catch up on a show that I'm watching on TV, or because I missed and episode. If I didn't pirate these shows then I probably wouldn't watch a lot of the shows that I do watch on TV because I wouldn't have caught up, or I would have been lost after missing a couple episodes.
In each case, I don't think my pirating has really denied anyone much revenue, and in many cases has increased revenue. Also I always spread the word about music, movies, or shows that I like.
Yes, it's theft, but in my mind it's not as big a deal, because I don't think I really deprive anyone of anything. If I stole bread, then someone else wouldn't have that bread, but if I steal a song, it's not as if they don't have that song anymore. Common sense tells you that it's illegal, and there's no use arguing technicalities like, "oh they just posted links" and such, but common sense also has me wondering if the adverse effects of pirating are overstated, and there are definitely positive effects of pirating that are largely ignored.