This is leaps and bounds better than the original version. It handles Iteration X as people, rather than some sort of abstract representation of control. In fact, with the Revised metaplot changes, Iteration X's worst aspects have been expunged, and now they're capable of becoming the same shades of grey that the other factions of Mage are able to be.
The first half of the book is the history of the world from Iteration X's point of view, along with other bits like how they view the Traditions and Conventions. It's told by a Virtual Adept who defected to Iteration X, which is certainly an interesting perspective, and directly calls the narrative of the first Iteration X book propaganda.
The remainder covers methodologies, beliefs, and then templates and Iteration X chronicles, along with a vast array of Devices (though no Procedures, which is a shame).