If we define the rules of the war on piracy as "provide a better product at a fair price" then the MPAA is actually WINNING the war on piracy. Just look at the "movies" that you might download from PTB, the few I've checked out are an excessively huge download with a crappy "taped by a two year old" movie in it. An actual DVD has a far superior viewing experience, a mess of extras and can be watched for as low as a dollar due to rentals. Unless you reaaaaly hate paying for things or you live in uzbekistan or china or some such place where a US dollar is enough to kill someone for, pirating movies isn't likely to be something you do often.
The problem with that theory is that bittorent, any site that contains torrents or links to torrents, and every single torrent program will be one of the first things to be blocked because some torrents are infringing. Part of the problem with PIPA is that it doesn't have any provisions for proving content is infringing, just an accusation of infringement is enough. And absolutely anyone can make that accusation. If microsoft were to make the accusation that ubuntu.com contained so much as a link to a site that may contain a link to pirate content, poof, no more ubuntu.