Unfortunately, the laws of thermodynamics say otherwise. The claim of Dr. Kanzius is that the energy output of the system is greater than the energy put into it. I'm disappointed that a mainstream news source like the Post-Gazette or CBS (where I also saw this) didn't bother to do the most basic scientific fact-checking.
The radio waves simply loosen the bonds between the hydrogen and oxygen and allow them to be easily broken when exposed to heat. That's all wonderful, and it seems like it's producing energy, except that the radio frequency generator he's using consumes several times more energy than the flame on the other end produces. Why no one has yet put a kill a watt on the other end of the RF generator, I'm not sure.
Yes, if we could burn salt water without energy inputs, the world would be a much better place. But the energy required to break the bonds of a molecule of water has always been greater than the energy produced by burning hydrogen and oxygen to create water, that's just the laws of physics, no conspiracy necessary to explain.
Bottom line, if he's come up with an energy efficient way to do work (weaken the bonds of salt water), it's still more economical to just use the energy he'd put into the system to power his toaster oven.