D-Wave does have a factoring algorithm.
See the comments from D-Wave here:
http://dwave.wordpress.com/2011/05/11/learning-to-program-th...
"We do have a factoring algorithm that I’m going to do a series of blog posts on"
http://dwave.wordpress.com/2011/05/11/learning-to-program-th...
"We do have a factoring algorithm that I’m going to do a series of blog posts on"
The truth is, D-Wave has done nothing to foster the coherence of their "qubits", and so they have built a very expensive, superconducting, classical computer. There is no quantum trick, actually. You have a system of buckets and you adjust the pipes and pumps between them so that in steady-state the water levels solve some problem you program in (with the pumps). Then you start in a random configuration, turn on the earthquake machine for a bit of randomness, and end up in the "ground state" solution.
The exponential speedup of quantum algorithms is sketchy enough: good luck performing an N-qubit logic gate, or in assuming that it's your favorite black-box that need only be executed a polynomial number of times (every quantum computing textbook uses their own set of universal gates). But these guys aren't even trying.
Scott Aaronson, the self-described "Chief D-Wave Skeptic", disagrees with you:
Now, I’d say, D-Wave finally has cleared the evidence-for-entanglement bar—and, while they’re not the first to do so with superconducting qubits, they’re certainly the first to do so with so many superconducting qubits. So I congratulate D-Wave on this accomplishment. If this had been advertised from the start as a scientific research project—”of course we’re a long way from QC being practical— —but we’ve shown experimentally that can entangle 100 superconducting qubits with controllable couplings”—my reaction would’ve been, “cool!” -- http://www.scottaaronson.com/blog/?p=1400
http://physics.stackexchange.com/questions/11063/can-quantum...
http://en.wikipedia.org/wiki/Qubit
PS: We have solid state 4bit quantum computers right now. They may not be useful for much, but that's in part because we have spent hundreds of billions of dollars perfecting classical computers.