Quote Originally Posted by archdreamer View Post
The value of these probability amplitudes are complex numbers with the sum of the squares of the moduli being equal to 1.
Actually the probability amplitudes are real numbers and are calculated as the mod-squared of the wavefunction, which is complex. /end nitpick

But yeah, I don't think quantum computers will ever be a replacement for classical computers because of the way they work. The programming is essentially the hardware itself, and it finds the answer by settling into the most probable set of positions. The areas will quantum computers will be useful are when a MASSIVE NP calculation has to be done that would take a classical computer weeks or more to do. Then it's worth building a quantum computer to do that calculation.