In New Zealand news today it is reported that the warrants for Kim Dotcom's raid weren't exactly legal. There have been a lot of reports of the weakness of the charges brought against Dotcom.
The reality is, having a strong case was never a priority to the FBI. It's just part of a crackdown effort. This tactic is not new, and
has worked in the past. I'm thinking of a piracy crackdown about 20
years ago. Back in those days, it was a network of dial-up bulletin boards, and
people who would commit phone fraud to upload and download data,
operating as couriers, in groups. The boards would often fund their
hardware through credit card fraud, and many of them made money selling
tapes full of pirated material.
The crackdown involved raiding the
boards, getting the user details, tracking the phone numbers of the users, and
getting various people raided in various countries. A lot of the
time the cases would collapse in court on various technicalities, but it
would be a year before people would get their seized computer equipment
back. The authorities in all the countries involved also learned who these people are, and how they go about their ways. The crackdown was a success.