700 IEEE Fellows surveyed in a joint study by the Institute for the Future (IFTF) and IEEE Spectrum tried to get the IEEE Fellows to predict science and technology over next 10 to 50 years.
One of the questions and responses was:
Will a quantum computer reach the market?
Equal chances 25.1%
This is addressed at the dwave blog. Dwave is planning a commercial release in 2007. They note that a company is selling a NMR based quantum computer for $1 million. The NMR system has little power and is probably being bought for research purposes. If you make a $1 million sale then you have commerce and you have reached a market.
Many people who comment on the response at the dwave blog and perhaps some of the IEEE fellows were reading the question as "Will quantum computers exceed the capabilities of traditional computers and outsell them in the marketplace". That would be a higher hurdle. The first part I think will definitely happen as we get 100-200 qubit systems. The outselling portion is a far more uncertain situation and probably is unlikely to happen. A fairly ideal situation would be for robust quantum computers to become co-processors for special needs along with regular computer systems.
I think most of the questions in the survey are poorly phrased and some of responses probably indicate reading the questions with certain unstated assumptions.
I also think many of the IEEE fellows may not be up to speed on the actual leading edge of capability for many technologies. Otherwise they would not make the mistake of stating that something is unlikely to happen in 50 years when it has already happened.