I don't think it's surprising that quantum computers, by themselves, will not be able to solve mathematical problems. Problem solving is not a feature of hardware per se, it is done by humans. Perhaps one day by AIs, too, if we can discover how to program them.
Two tantalising potential benefits of Quantum Computers:
(1) the ability to model all kinds of matter efficiently at the molecular level which will spur the development of nanotech
(2) people will ask 'Where are these humongous computations being performed?' and then embrace the 'many worlds interpretation' of quantum mechanics, which will in turn create further scientific and philosophical progress
For a nice description and diagram, take a look at the wiki page. http://en.wikipedia.org/wiki/Quantum_computing#Relation_to_c...
"In a 5 year period we get one superb programming language. Only we can't control when the 5 year period will be."
They said this fifteen years ago on a radio broadcast. I was sitting there. I heard it.
Now, for the last time, where is my jetpack?