There are a variety of factors at play in this decision, some philosophical and some practical. On the philosophical side, We believe that teaching modern web app development is better facilitated by leveraging JS. From a practical perspective, JS is integral to modern app development. JS runs in every browser on the planet. JS is the #1 language on GitHub and it's the most sought-after skill among start-ups here in Colorado.
Why Angular.js? Angular is killing it. Read me here.
Ultimately, RefactorU is teaching a broader skill set of how to be an effective programmer and how to learn new technologies. The specific languages used to do that have been selected both for the excellence of programming skills their fans typically acquire, and for their demand and applicability in the market. The people who care to invest their time learning more cutting-edge languages show passion and technical maturity that the average CS graduate may not. We also think our approach is the most efficient route available to those deeper technical skills.