The method is based on a chemical reaction ceramics have with water over long periods of time. Basically they absorb it (I'm not sure if this holds true for buried ceramics) at a particular rate that can be used to estimate the time since the ceramic was fired.
The examples given on the BBC website suggest that this could be incredibly precise. To the year! They know it works going back 2000 years and suspect it works as far back as 10,000. If the technique passes through its age of innocence and comes out the other side as a reliable dating method it could literally revolutionise our understanding of most archaeological periods in Ireland (and many other regions).
Apparently the paper will be published online soon in the Proceedings of the Royal Society A and I personally will be waiting with baited breath!