From what I gathered so far, this is more of a theoretical win for mathematicians, computer scientists, and physicists because it basically proved that if you had two Q-computers with unbounded (read: greater than infinite, basically) power, they could convince a classical computer in poly time that they could run a Q-program to completion correctly, in infinite time.
So basically, we would still need a way to build an unboundedly-powerful pair of Q-computers that were entangled (whoops, forgot that part!) in order to get any direct application for this, then we'd have to actually write the software to run this series of communications the 3 computers exchange from the paper.
So, this is only useful for some unknown, future proof of something else, not to engineer a real-life system with.