"The interesting thing about such a value is that it could be used to determine the correct value of any problem simply by casting it to the appropriate data type."
This is incorrect. Determining the superposition's state won't give you the correct answer. It will give you a random answer from all of its possible states -- weighted by the chance of that being the right answer. This makes quantum computing much trickier.
http://scottaaronson.com/blog/?p=208 is a great article if you want to understand how some Quantum algorithms we know of will work using this "probable-answer" property.
We will have solar energy as soon as the utility companies solve one technical problem -- how to run a sunbeam through a meter.