It turns out it's a little tough to work out whether or not D-Wave's quantum computer is actually doing anything, well, quantum. Fantastic write-up here from Ars Technica, but the short version:
D-Wave's method of doing quantum computing makes it engineering-feasible, and somewhat scalable, but tough to tell if it's actually doing anything quantum-like. Testing if any "spooky-action-at-a-distance" is actually happening inside the system can't really be done, and whether or not quantum tunneling is actually happening only really comes down to whether it PERFORMS better than a classical computer at solving certain tasks that should be faster to perform on a quantum computer.
D-Wave, NASA, and Google's most recent paper and press releases show that it is performing better than the worst classical algorithm, but it's not performing better than the best. So it's a point in the right direction, but not an entirely definitive smoking gun.
Thoroughly mind-bending reading below: