That is quantum cryptographic not quantum computing. It isn't used for breaking encrypted messages, it is the holy grail of secure key exchange with no algorithm weaknesses.
Simple version is that a large one time random key can't be broken. There is no algorithm weakness, no method of attack except brute force, and if the key is large enough brute force becomes infeasible. Quantum cryptography (namely quantum key sharing) allows the creation of a shared secret between two parties who can't be eavesdropped. Once two parties have a mutual random secret key they can communicate over normal methods with absolutely no risk of attack. An attacker could record everything that is being transmitted and it would be useless forever. Not 10 years or 10,000 years but forever. There is no weakness which can be found, no crypto-analysis which can eventually unlock the secret.
http://en.wikipedia.org/wiki/Quantum_key_distributionQKD has been around a long time but this if the first widespread usage of it I have heard about.
