I would just like a recap of the story for a layman. You know the sort of thing one would do to explain a computer system to his mother. The sort of thing Brian Greene does to explain string theory to the masses.
D-Wave is trying to make use of the quantum properties of matter in order to solve a particular kind of problem. They want to find the ground state (lowest energy) configuration of spins (a non-classical degree of freedom) in a 2D lattice composed of N atoms. Each atom is allowed to interact with its neighbors obeying rules that are defined by the way the computer is built.
They're essentially setting up a number of "qubits" (which is not related to "binary digit" other than they're both units of information) to naturally converge on the lowest energy state. All the qubits need to be entangled (fundamentally linked) in order for the system to work. This is a necessary but insufficient condition for quantum efficiency gains, which is the point Mr. Aaronson is making. The computer is not, according to recent evidence, providing computational gains. He then goes into the details, which you might or might not be interested in.
If you have other questions, please ask. I'm not an expert, but I understand his argument.
