The potential power of quantum computing comes from the possibility of performing a mathematical operation on both states simultaneously. In a two-qubit system it would be possible to compute on four values at once, in a three-qubit system on eight at once, in a four-qubit system on 16, and so on. As the number of qubits increases, potential processing power increases exponentially. ...So if this were correct, then he would be able to compute 256 values at once, in a year or so.
The Santa Barbara researchers said they believe they will essentially double the computational power of their quantum computers next year.
John Martinis, a physicist who is a member of the team, said, “We are currently designing a device with four qubits, and five resonators,” the standard microelectronic components that are used to force quantum entanglement. “If all goes well, we hope to increase this to eight qubits and nine resonators in a year or so.”
Don't bet on it. I don't think that they have even proof of one genuine qubit really doing two computations at once.