One of the biggest file sharing, Megaupload has been taken down by FBI because they take financial advantage from illegal files that are being shared by their users and also from advertising (up to $175 million). Even though they have signed up DMCA agent with the US government, provide an abuse tool, and given rightsholders access, they are still taken down by the FBI.
This event doesn't stop like that. While most users that have Megaupload premium account can't do anything about it, Anonymous group launched a retaliation attack to several US sites, such as DoD and Universal Music Group. They will launch another attack on MPAA and also on White House, and probably many US sites in the future.
If Megaupload can be taken down so easy, what about the others? There are still a lot of file sharing services out there that have the same (or similar) business process with Megaupload, but they are still operating at this moment.