Why FBI's Carnivore was "retired"

At Volokh Conspiracy, Orin Kerr on why the FBI "retired" the 'net surveillance project known as Carnivore:

The Fake Carnivore Debate, RIP: The Associated Press reports that the FBI has retired its "Carnivore" Internet surveillance tool. (It actually happened about two years ago, but no one knew about it until now.) The Carnivore debate was premised on a profound misunderstanding of Internet surveillance practices. With the Carnivore era over, it's a good time to look back at how the press was able to get the story so wrong.

Link (via politech, where you'll find lots of background on Carnivore.)