I'm assuming they break things down into traditional objective units within a standard curriculum and material that is relevant.
That's great but it is a very manual process.
Remember Yahoo curated keyword recommendations from the 90s? This Knewton approach is more like that. What I'd like to see is more like a Google Search in this analogy...something more flexible and comprehensive.
The basic idea is that you might start with a manual linkage between concepts, derived from linkages between content developed by subject matter experts, but over time it organically morphs into a knowledge graph that describes how certain concepts relate to and build on each other, and for which scenarios of learners.
That knowledge graph combined with a concrete goal (mastery level) and time to get there (deadline) can then be used to recommend to a specific learner what material to study or activities to do next.
It's theoretically possible to do this even more organically, but you need clearly tagged educational "stuff" (written content, lectures, activities, etc.) and, perhaps more importantly, clear ways to measure outcomes as a result of interacting with that "stuff" (typically quizzes which themselves have been clearly calibrated).
