Shit hit the fan on Thursday; the U.S. government took down Megaupload, one of the largest file-sharing sites in the world. Here’s a quick recap of the key events in this crazy story:

• Megaupload is one of top 100 most-visited websites on the web for years, mostly because it was an easy and relatively “safe” way to download and transfer pirated content. Yes, people hosted legal stuff there, but the vast majority of it was pirated.
• On December 9, a bizarre video was released with A-listers seemingly endorsing Megaupload. P Diddy, Will.i.am, Alicia Keys, Snoop Dogg, Kanye West were among the stars featured.
• Universal and the RIAA were NOT happy with this, so they asked YouTube to take it down due to copyright infringement,. They succeeded, though Megaupload continued to host the video (YouTube eventually brought it back as well). Megaupload essentially gave the music industry the middle finger.
• Everything exploded yesterday, though. The FBI led a coordinated strike against Megaupload that involved 20 search warrants in eight countries. The result was the shutdown of Megaupload.com and the seizure of more than $50 million in assets.
• Megaupload’s staff was also arrested and denied bail in New Zealand. This includes founder and majority owner Kim Schmitz — aka Kim Dotcom. Yes, that’s what he goes by.
• Here are some pictures of the New Zealand government confiscating the Megaupload team’s very fancy cars.
• Oh, and it was revealed that Swizz Beatz is the company’s acting CEO. Yes, the guy who’s married to Alicia Keys. This was likely an attempt by Kim Dotcom to reduce the heat on himself.
• GigaOm has a fantastic summary of the indictment itself, if you want to learn more.
• There was an important part of the Internet that didn’t like how this raid went down though: Anonymous. The shadowy hacker group launched its largest attack ever merely minutes after the raids became public. They attacked “the White House, the FBI, the Department of Justice, multiple record label sites, the MPAA, and RIAA, and the U.S. Copyright Office” all at once. Anonymous considered the destruction of Megaupload an act of war, and they responded with an all-out counterstrike.

If you think today is the worst of the retaliation, then you’re deluding yourself: Anonymous is nowhere near done. The IRC chatrooms where Anonymous plans its attacks are still active. I suspect that it will continue to lash out as more details of the Megaupload takedown come to light.

Questions remain: will Megaupload’s leaders be extradited to the U.S.? Where are pirates going to store files now? What is Anonymous’s next move?

The fireworks are just beginning, so find the nearest bunker, because yesterday was just the first of many battles in the Great Megaupload War of 2012.