D-Wave isn't trying to build a general purpose quantum computer. As it stands, they've been trying to optimize a computer that executes a particular algorithm

D-Wave isn't trying to build a general purpose quantum computer. As it stands, they've been trying to optimize a computer that executes a particular algorithm (and as it stands, it's not faster than optimized classical algorithms). It is an open research question if D-Wave's architecture actually utilizes any quantum effects to give it an advantage over classical architectures. D-Wave hopes that there will be enough problems that their machine is good at that their approach will be justified. D-Wave markets themselves as having hundreds or thousands of qubits, but these qubits aren't easily controllable or measurable in ways that would allow Shor's to be executed on them (for example), so at the least, it seems like dishonest marketing. In order to build a general quantum computer, you need to be able to apply gates to arbitrary collections of qubits. I'd recommend everyone to check out IBM's online http://www.research.ibm.com/quantum/ http://www.research.ibm.com/quantum/ for a brief tutorial on how you need to be able to wire qubits together, and what a general quantum computer would look like. (You can even execute the result on an actual Quantum Computer; so it gives some idea of what an API would look like).