The motion is here (pdf). Media coverage to follow, undoubtedly, but the first paragraph sets the tone:
This is not a case about one isolated iPhone. Rather, this case is about the Department of Justice and the FBI seeking through the courts a dangerous power that Congress and the American people have withheld: the ability to force companies like Apple to undermine the basic security and privacy interests of hundreds of millions of individuals around the globe. The government demands that Apple create a back door to defeat the encryption on the iPhone, making its users’ most confidential and personal information vulnerable to hackers, identity thieves, hostile foreign agents, and unwarranted government surveillance. The All Writs Act, first enacted in 1789 and on which the government bases its entire case, “does not give the district court a roving commission” to conscript and commandeer Apple in this manner. Plum Creek Lumber Co. v. Hutton, 608 F.2d 1283, 1289 (9th Cir. 1979). In fact, no court has ever authorized what the government now seeks, no law supports such unlimited and sweeping use of the judicial process, and the Constitution forbids it.
Update: As expected, there is tons of media coverage of the motion. Head to your favorite news analysis site to read up. Or for the tl;dr version, see Shawn Tuma’s recap of the motion in less than 300 words.