Phoenyx Imperius says: I don't think the FBI's attack on Megaupload was legal. Sure, Megaupload made a lot of money, sure, people used it to upload copyrighted works, but Megaupload is based in New Zealand, outside the FBI's jurisdiction. New Zealand should have been responsible for taking them down, but they aren't.
... says: The indictment was returned in the Eastern District of Virginia, which claimed jurisdiction in part because some of the alleged pirated materials were hosted on leased servers in Ashburn, Virginia. Prosecutors there have pursued multiple piracy investigations. (source)