They call it "nano spray-on antenna material." That description is sort of vague. What Chamtech came up with is a a liquid filled with millions of nano-capacitors. In May of 2012 they did a presentation as part of the ARRL's DIY series at the Dayton Hamvention. Wired gave them a write up a couple months ago as well. They are not the first to claim they can spray on an antenna. J-walk.com did [here] but only in jest. But the idea is not completely crazy.
The problem is that Chamtech hasn't explained how their product works. Tyler Holman at Neowin.net stated the problem simply "A traditional antenna would require thousands of watts to send out a signal with a one mile range underwater. Chamtech's can do that with only three watts, and have a stronger signal to boot. So how does all of this work? The truth is, we don't really know." This phenomena can happen. Lee DeForest infamously didn't' understand how his own triode tube worked. It was Edwin H. Armstrong who later explained it.
Anthony Sutera (above) gave a talk on Google's Solve for X series and described their spray-on material as very heat efficient and functioning in a fundamentally different way from a normal aerial. But their broad unsubstantiated claims have left many engineers incredulous. Nanocapacitors are a relatively new technology. They debuted in 2009. He describes energy hopping from capacitor to capacitor, then working underwater, then being self-powered, improving the efficiency of the electrical grid, and doing everything except making you a BLT. It's this over-promising that spoils the show leaving me incredulous too.