[themgt]

I think Aaronson's Q&A w/ MIT News is the most accessible explanation of why this isn't an "it works!" moment. It's a complex, nuanced argument so it's easier to just read than try to summarize here [1]

I think basically if you grasp why Selby's algorithm is able to beat D-Wave, you'll understand why D-Wave isn't a useful quantum computer, whatever terminology you want to use to describe it.

N.B. Even Aaronson admits D-Wave may have useful technology[2], it's just that the present "dirty qbit" approach doesn't give you a machine useful for anything more than basic science research, which is not at all how D-Wave have hyped it.

[1] http://news.mit.edu/2015/3q-scott-aaronson-google-quantum-co...

[2] http://www.scottaaronson.com/blog/?p=2555#comment-967324